Satellite Orbits — Principles, Workflow & Capability Walkthrough

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1. Principle Assessment Rubric

How each of the six Guiding Principles is measured. The last column states the calculation method, not the resulting figure — walk through the method live, then state the number.

Methodology note: Principles 3, 4, and 6 use the domain-average approach designed this session (Governance & Strategy / Data Management / Engagement & Collaboration), which supersedes the qualitative Governance Risk Track (Part D) published in WA1b for those three principles. This is a deliberate methodology change, not a formatting choice — flag it as such if asked. Principles 1, 2, and 5 are unchanged from the published rubric.

Principle	Assessed via	Data source / domain	Scope	How the score is calculated	Satellite Orbits — result
1. Geographic Distribution	Workflow topology	Site and institution geography — hemisphere coverage, ODC/RDC/GDC locations	Product-specific	Step Criticality (1–5), per WA1b's conceptual framework — physical/geographic redundancy scarcity raises the score. Multiplies against the Principle 5 PPTD Gap: Tier Risk Score = PPTD Gap × Step Criticality see 5 below for a detailed explaination and example of the PPTD Gap	Criticality ranges 2–5 across the 5 tiers; peaks at 5 on Tier 3 (ACC/SPOCC — single point of failure)
2. Political Resilience	Workflow topology	Political jurisdiction count per tier — host country of archiving and combination institutions	Product-specific	Count of independent political jurisdictions hosting redundant capacity per tier; flag if fewer than 2	Flagged at Tier 1 (GDC network: only 2 jurisdictions, USA/France) and Tier 3 (all 12 accountable individuals: USA/Europe/Australia only)
3. Centralised Accountability	Capability model (supersedes Part D)	Governance & Strategy domain average (14 capabilities: Mandate, Risk Management, Performance Management, Strategic Planning, etc.)	Baseline supply-chain-wide (1.76); product-specific where a departure is validated	Domain average, then re-assessed per capability against product-specific evidence (dimension-level, not aggregate). Satellite Orbits: Mandate re-asserted 1.00→1.50 (named ACC Co-Leads, no formal charter) → domain average 1.80	1.80 (vs. 1.76 baseline)
4. Technical Interoperability	Capability model (supersedes Part D)	Data Management domain average (19 capabilities)	Baseline supply-chain-wide (2.75); product-specific where a departure is validated	Domain average, then re-assessed per capability. Satellite Orbits: GNSS Data Processing and Analysis People 4.00→3.00 (unaddressed succession gap, explicit in annex); Data Preservation Process 2.00→1.00 (untested GDC failover) → domain average 2.72	2.72 (vs. 2.75 baseline)
5. Minimum Capability Maturity	Capability model	Worst-tier PPTD average (People / Process / Technology / Data)	Product-specific	PPTD Gap = 5 − average maturity of the tier's capabilities, taken at the worst-scoring tier. Example — Satellite Orbits Tier 3: five capabilities (Geodetic Data Products 2.75, Performance Management 1.00, Risk Management 0.50, Disaster Recovery 1.25, Knowledge Management 1.25) average to 1.35 → Gap = 5 − 1.35 = 3.65 (feeds the 18.25 Tier Risk Score). NA = 0 convention: where a dimension doesn't apply to a capability (e.g. Risk Management has no distinct Technology or Data dimension), it is scored 0 and included in that capability's four-dimension average — a deliberate, conservative choice; averaging only applicable dimensions instead would raise the tier average to 1.73 and lower the score to 16.35 (still #1, still High). The annex table has been corrected to display this convention consistently	Tier 3 Gap 3.65 → Tier Risk Score 18.25 / 25 (High) — highest of all 25 tiers across all 5 products
6. Transparency & Accountability	Capability model (supersedes Part D)	Engagement & Collaboration domain average (6 capabilities)	Supply-chain-wide (2.13) — assessed, no departure supported	Straight average of the 6 domain capability scores. Assessed and considered this session; evidence for the strongest candidate (Stakeholder Identification and Analysis) was ambiguous, not absent — see §4 for why it wasn't asserted	2.13 (baseline, no departure)

Only Principles 1 and 5 feed the numeric Tier Risk Score = PPTD Gap × Step Criticality formula used for investment ranking. Principles 2, 3, 4, and 6 do not — they're read independently, alongside the score, not multiplied into it.

Step Criticality scale (WA1b, Part B) — an integer 1–5 representing a workflow step's structural importance to product delivery, independent of maturity. It measures redundancy: whether an alternative pathway exists if the step fails.

Score	Definition	Example
5	Single point of failure — no substitute pathway exists globally; failure terminates product delivery	ACC/SPOCC (Satellite Orbits Tier 3)
4	Dominant path — one primary institution; alternatives exist but aren't operationally ready	ITRS Combination Centre at IGN (ITRF Tier 3)
3	Important but substitutable — meaningful redundancy across multiple institutions	IGS Analysis Centres (13 independent centres)
2	Supported — multiple parallel, fully operational institutions	Global Data Centres (CDDIS, IGN, SIO)
1	Redundant — loss is easily mitigated; many alternatives available	Individual GNSS stations in high-density regions

Two scoping decisions confirmed this session: Principle 4 uses the Data Management domain only, not Asset and Infrastructure Management — interoperability is a data/systems question, and physical asset resilience is already Principle 1's territory. A proposed new capability for Principle 6, "Stakeholder Disclosure & Public Reporting," was not added — the State of Geodesy 2026's 58-capability model is this methodology's credibility anchor, and adding a capability outside it would need its own primary-source validation before it could carry a defensible score. Logged as a candidate for the next SoG capability model revision cycle, not scored here.

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2. Satellite Orbits Workflow — Updated

What this diagram shows: how raw signals from GPS, Galileo, GLONASS, and BeiDou satellites become one official, trusted "satellite orbit" product — the dataset that tells anyone, at any moment, exactly where a satellite actually is. Read it top to bottom, one step at a time: ground stations collect the raw signal, data centres receive and store it, analysis centres turn it into a usable answer, one final combination step merges everyone's work into a single authoritative product, and that product gets checked and released. Each step's colour tells you how risky it is — red is the most concerning, blue is fine. Next to each step, we also show which specific capabilities (people, processes, technology, or data) that step actually depends on, and which organisation is responsible for keeping it running. The point of walking through it this way is to make it obvious where in this chain things could go wrong, not just that something, somewhere, might.

How to read the mechanics below, for anyone who wants the construction detail: same tier structure and institutional detail as the published annex (v5.5) — RDC/GDC/ODC counts unchanged. Governance is its own consistent column on the right of every row — scan straight down to see which body governs which tier. Principle 1 and Principle 2 gaps are shown as flagged lines attached to the tier they apply to, since those two are computed per-tier. Principle 3 is a single supply-chain-wide score, not tier-by-tier, so it can't be flagged the same way — but the governance column carries a P3 evidence note wherever a tier's narrative fed the Mandate assertion or shows a comparable governance gap. Principle 4 is also a supply-chain-wide average, but the annex ties two specific findings to specific tiers — both shown as flags: Tier 1 (no FAIR-compliant data source registries) and Tier 2 (intermediate AC solutions not archived per FAIR Principle 4). Tiers 0, 3, and 4 have no equivalent P4-tagged finding in the annex text. Principles 5 and 6 aren't tier-specific enough to annotate per row; they're covered in §1 and §3.

Governance hierarchy: IGS Governing Board (policy) → IGS Central Bureau (operational coordination) → IGS Infrastructure Committee (technical standards). Capabilities on the left are the exact inputs to each tier's Principle 5 PPTD Gap; chips on the right show which body governs each tier and how.

Capabilities

Workflow

Governance

No capabilities (external input)

Pre-TierConstellation Operators

External inputs

GPS
US DoD

Galileo
ESA

GLONASS
Russia

BeiDou
China

No IGS governance layer — external input

Ground-Based Asset Management — 2.50

Equipment Calibration and Maintenance — 2.50

Network Operations — 2.00 (shared with Tier 1)

Tier 0Data Acquisition & First-Mile Telemetry

8.00 / 25 · Significant (P1×P5)
2.67 × 3

106 of 107 Core Sites (GNSS)
553 Std Sites

Operational Data Centers ×3
GFZ · CNES REGINA · NGS/NOAA

⚠ P1 — All 3 ODCs in Northern Hemisphere

IGS Central Bureau

Standards

IGS Infrastructure Committee

Network standards

P3 gap: CB hosting at JPL rests on no formal MoU

GNSS Data Acquisition and Storage — 3.50

Network Operations — 2.00 (shared with Tier 0)

Data Quality Management — 2.00

Metadata Management — 2.00

Data Preservation — 2.00

Tier 1Global Archiving & Data Hierarchy

10.80 / 25 · Significant (P1×P5)
2.70 × 4 (was 3)

Regional Data Centers ×4
BKG · GA · KASI · SOPAC

Global Data Centers ×3
CDDIS · IGN · SIO

⚠ P2 — GDC network: only 2 jurisdictions (USA, France)

⚠ Untested — Failover to IGN/SIO — no drill on record

⚠ P4 — No FAIR-compliant, publicly documented data source registries (also P6)

IGS Infrastructure Committee

Archiving standards

P3 gap: no SLA/MoU governs GDC equalization failover

GNSS Data Processing and Analysis — 3.75

Geodetic Software and Tools — 2.00

Knowledge Management — 1.25 (shared with Tier 3)

3.75 is the baseline — the 3.50 asserted for P4 isn't reflected in this Tier Risk Score yet

Tier 2Analysis Centres & Software Ecosystem

8.00 / 25 · Significant (P1×P5)
2.67 × 3

13 Global Analysis Centres
JPL · CODE · ESA/ESOC · GFZ · Wuhan +8

Individual Orbit Solutions

⚠ P4 — Intermediate AC solutions aren't archived per FAIR Principle 4; Tier 3 combination can't be independently reconstructed or audited

IGS Central Bureau

Coordination

P3: no direct governance gap evidenced at this tier

Geodetic Data Products — 2.75

Performance Management — 1.00

Risk Management — 0.50

Disaster Recovery and Supply Chain Continuity — 1.25

Knowledge Management — 1.25 (shared with Tier 2)

Tier 3EGV Combination — Critical Bottleneck

18.25 / 25 · HIGH (P1×P5)
3.65 × 5 · highest of all 25 tiers

ACC
GA + NASA GSFC

SPOCC Engine
GFZ

Ultra-Rapid · Rapid · Final

⚠ P2 — ACC transitioning to NASA GSFC — US jurisdiction risk, no formal backup

⚠ P1 — All 12 accountable individuals: USA / Europe / Australia only

IGS Central Bureau

Governance

P3 gap: no formal ACC charter — drives the Mandate assertion (1.00→1.50)

Geodetic Services — 2.00

Regulatory Compliance — 3.00

Standards Development and Promotion — 3.00

Data Distribution (2.00) is in the published annex table but doesn't feed this tier's Gap

Tier 4Validation & Distribution

4.67 / 25 · Minor (P1×P5)
2.33 × 2

IERS Validation

IGS Distribution

End Users +
L3 EGV Pipelines

Not governed — Tier 4 not currently in UN-GGCE risk register

GGOS / IAG

Reports to (Coordination)

P3 gap: no SLA-based performance monitoring at validation/distribution

Risk classification: High Significant Minor Pre-tier / external

Note on scope: the Regional Data Centre count (×4) is left exactly as published. A discrepancy was found this session — the knowledge graph lists 8 RDCs (all IGS-sourced), and a direct check of igs.org returned a third, different count — but three disagreeing sources is not enough to correct the annex on. Flagging verbally in the walkthrough is safer than a silent change; proper reconciliation (raw-HTML source check, not AI-summarized) is a follow-up item.

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3. Capability Model — Satellite Orbits

This scoping shows the 18 capabilities that actually feed the Satellite Orbits workflow annex's tier computations, plus Mandate (marked †) — a product-specific addition, not yet in the published annex — of 58 total in the model. (SLR and DORIS Data Acquisition and Storage were removed from this scoping this session — they're VLBI/SLR/DORIS multi-technique capabilities that don't apply to Satellite Orbits, a GNSS-only product; they'd previously been carried over from a shared template.) Of these 19, 16 are the unmodified State of Geodesy 2026 supply-chain-wide result; 3 (marked †) are product-specific departures for Satellite Orbits, each validated to the individual PPTD dimension rather than adjusted as a single number: Mandate (1.50, vs. 1.00 baseline), GNSS Data Processing and Analysis (3.50, vs. 3.75), Data Preservation (1.75, vs. 2.00). See §4 for the dimension-level justification behind each.

Source: State of Geodesy 2026 (UN-GGCE, 16 March 2026), cross-checked against the supply chain's capability database on 15 June 2026.

← Scroll horizontally to view all six domains → · † = product-specific assertion, differs from the supply-chain-wide baseline · greyed/italic = not cited for Satellite Orbits (score shown is the supply-chain-wide baseline, for context only) · gold/dashed = proposed new capability, not yet in the 58-capability model

1. Engagement and Collaboration

Education and Outreach

Curriculum Development and Educational Program Delivery2.00

Outreach and Public Awareness1.30

Government, Science, Academic and Private Sector Collaboration

Partnership and Collaboration2.00

Standards Development and Promotion3.00

Stakeholder Management

Stakeholder Communication and Engagement2.00

Stakeholder Identification and Analysis2.50

Stakeholder Disclosure & Public ReportingPROPOSED

2. Governance and Strategy

Domain avg (supply-chain-wide): 1.76 · Satellite Orbits (asserted): 1.80

Financial Management

Budgeting1.00

Cost Management1.00

Funding and Investment1.00

Policy and Regulation

Legal Framework2.00

Mandate †1.50

Policy Formulation1.00

Regulatory Compliance3.00

Risk and Security Management

Cyber Security Management3.00

Disaster Recovery and Supply Chain Continuity1.70

Physical Security Management3.00

Risk Management1.00

Strategy and Planning

Performance Management2.00

Strategic Planning1.00

Vision and Strategy3.00

3. Data Management

Domain avg (supply-chain-wide): 2.75 · Satellite Orbits (asserted): 2.72

Data Acquisition and Storage

DORIS Data Acquisition and Storage4.00

GNSS Data Acquisition and Storage3.50

Gravity Data Acquisition and Storage3.30

Local Tie2.00

SLR Data Acquisition and Storage3.00

VLBI Data Acquisition and Storage3.00

Data Dissemination and Access

Data Distribution2.00

Data Preservation †1.75

Data Sharing3.00

Data Governance

Data Architecture Design2.30

Data Lifecycle Management2.00

Data Quality Management2.00

Metadata Management2.00

Data Processing and Analysis

DORIS Data Processing and Analysis3.80

GNSS Data Processing and Analysis †3.50

Gravity Data Processing and Analysis2.80

Local Tie Processing and Analysis2.00

SLR Data Processing and Analysis3.50

VLBI Data Processing and Analysis2.30

4. Data Products and Software

Delivery and Support

Geodetic Services2.00

Training and Education1.70

Product Development and Maintenance

Geodetic Data Products2.80

Geodetic Software and Tools2.00

Reference Frames3.00

5. Asset and Infrastructure Management

Calibration and Maintenance

Equipment Calibration and Maintenance3.30

System Testing and Validation2.50

Geodetic Infrastructure Management

Ground-Based Asset Management2.50

Model of the Global Geodesy Supply Chain1.00

Network Operations2.00

6. Innovation and Development

Innovation Management

Innovation Project Management2.80

Innovation Strategy Development1.00

Research and Development

Knowledge Management1.30

Research and Development Execution2.30

Research and Development Planning1.50

Research and Development Prototyping3.00

Technology Adoption and Integration

Technology Assessment2.50

Technology Integration2.80

Technology Scouting1.80

Maturity score (PPTD avg): 4–5 · No significant deficiency 3–4 · Minor gaps 2–3 · Significant gaps 1–2 · Critical deficiency — · Not yet assessed† Product-specific assertion — differs from the supply-chain-wide baseline Greyed/italic · Not cited for Satellite Orbits Gold/dashed · Proposed, not yet in the model

(Maturity scores are drawn from the published State of Geodesy 2026 assessment and cross-checked against the supply chain's capability database, re-verified 15 June 2026. Full 58-capability model shown for context — greyed entries are the supply-chain-wide baseline score for capabilities not evidenced in the Satellite Orbits annex; 19 of 58 are actually cited or asserted for this product, 39 are shown for comparison only. "Stakeholder Disclosure & Public Reporting" under Engagement and Collaboration is a proposed 59th capability — not scored, not in the published State of Geodesy 2026 model, raised this session as a Principle 6 candidate and logged for the next model revision cycle rather than added unilaterally.)

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4. Assertions Supporting the Satellite Orbits Maturity Assessment

Confirmed — cited directly in the published annex (18 of 58 capabilities, 31%):

(The bracketed number after each tier is how many capabilities are listed at that tier. Network Operations is cited at both Tier 0 and Tier 1, and Knowledge Management at both Tier 2 and Tier 3 — each the same capability, evidenced in two places — so the five tier counts sum to 20 but the unique confirmed total is 18. Tier 0 and Tier 1 were corrected this session: GNSS Data Acquisition and Storage moved from Tier 0 to Tier 1 — its score reflects storage/archiving, not first-mile acquisition — and SLR/DORIS Data Acquisition and Storage were removed entirely, since they're multi-technique capabilities that don't apply to this GNSS-only product.)

• Tier 0 (3): Ground-Based Asset Management, Equipment Calibration and Maintenance, Network Operations
• Tier 1 (5): GNSS Data Acquisition and Storage, Network Operations (shared with Tier 0), Data Quality Management, Metadata Management, Data Preservation
• Tier 2 (3): GNSS Data Processing and Analysis, Geodetic Software and Tools, Knowledge Management
• Tier 3 (5): Geodetic Data Products, Performance Management, Risk Management, Disaster Recovery and Supply Chain Continuity, Knowledge Management (shared with Tier 2)
• Tier 4 (4): Geodetic Services, Data Distribution, Regulatory Compliance, Standards Development and Promotion

Asserted — product-specific departure from the shared baseline, validated to the PPTD dimension level (3 of 58 capabilities):

• Mandate, 1.00 → 1.50 (Principle 3). Global baseline: People 1.00, Process 1.00 (no Technology/Data dimension — governance-only capability). Satellite Orbits: People raised to 2.00 — a named, staffed role exists (ACC Co-Leads Salim Masoumi and Tom Herring), evidenced in the annex's Tier 3 narrative; not a hypothetical. Process held at 1.00 — no formal charter establishes the ACC's mandate; the annex explicitly states no formal backup ACC exists and the 2013 NRCan/ESA contingency "has never been formalised, contracted, or rehearsed." New average: (2.00 + 1.00) / 2 = 1.50. Same rigor standard as the Satellite-Orbits-vs-ICRF governance pilot earlier this session (where ICRF's equivalent Mandate score stayed at the 1.00 floor — no designated body exists there at all, not even an informally staffed one).

• GNSS Data Processing and Analysis, 3.75 → 3.50 (Principle 4). Global baseline: People 4.00, Process 4.00, Technology 3.00, Data 4.00. The annex states directly: "The Process dimension of GNSS Data Processing and Analysis scores 4.00 at the pipeline level; however, succession planning is not formalised across AC teams" — evidence for the People dimension, not Process, since the annex itself reaffirms Process at 4.00. Satellite Orbits: People lowered to 3.00, others unchanged. New average: (3.00 + 4.00 + 3.00 + 4.00) / 4 = 3.50.

• Data Preservation, 2.00 → 1.75 (Principle 4). Global baseline: People 2.00, Process 2.00, Technology 2.00, Data 2.00. Same evidence base as the Step Criticality revision on this tier: "no deliberate failover drill, disaster-recovery exercise, or business-continuity test... appears anywhere," and BKG "has openly reported having no disaster recovery capability" — direct evidence against the Process dimension (absence of a tested, documented continuity procedure), not People, Technology, or Data. Satellite Orbits: Process lowered to 1.00, others unchanged. New average: (2.00 + 1.00 + 2.00 + 2.00) / 4 = 1.75.

Combined unique coverage: 19 of 58 capabilities (33%). Not simply 18 + 3 — GNSS Data Processing and Analysis and Data Preservation are already inside the confirmed 18; Mandate is the only asserted capability that's net new.

Considered and not asserted — evidence exists but doesn't cleanly support a departure (1 capability):

• Stakeholder Identification and Analysis (Principle 6 candidate) — global baseline People 3.00, Process 2.00, Technology 2.00, Data 3.00, avg 2.50. The annex's 12-person Stakeholder Accountability Matrix is real evidence of clear role definition (arguably supports the score as-is), but the matrix's own "11 of 12 succession status: not documented" finding is evidence for a different capability (Training and Education) — folding it into this one would repeat the exact error corrected earlier in this session on Performance Management. Left at baseline deliberately, not by omission.

Queued — evidenced in the annex's prose, not yet added to the capability tables, not yet dimension-level rated (6 capabilities). Deliberately not scored under time pressure; treat as a to-do, not a finding:

• Policy Formulation — Governance table, IGB row: "strategic direction and policy authority for the IGS"
• Funding and Investment — "no guaranteed funding continuity" (Tier 2, AC teams); funding-change risk at EarthScope/GFZ (Tier 0, IC personnel)
• Legal Framework — "no formal MoU" governing CB hosting at JPL (Tier 0); no SLA/MoU/trigger criteria for the NRCan/ESA contingency (Tier 3)
• Training and Education — near-universal succession-gap flags (⚠) across the Stakeholder Accountability Matrix — the single most-repeated finding in the document
• Reference Frames — Overview: "SPOCC uses Helmert transformations anchored to the current ITRF" — a direct, explicit dependency
• System Testing and Validation — Tier 4: IERS "independent validation... against the current ITRF"

If asked in the room why these 6 aren't scored yet: the honest answer is that scoring them properly means the same per-dimension check the three asserted capabilities went through, not a quick aggregate guess — that's deliberately not rushed the morning of a stakeholder walkthrough.

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5. Proposed Workshop Approach

A proposal, not yet agreed — drafted from the 14 Aug discussion with Nick on how to run the product working-group consultation. Intended to be stress-tested and revised, not run as-is. Two separate bodies with two separate, non-overlapping jobs — the product working groups aren't asked to touch the principles-level rubric at all; that complexity sits with a governance committee instead.

5.1 Product Working Groups — per product, capabilities and workflow only

Who: one group per product, not organised by technique or country. Deliberately cross-industry — Nick's own framing: IAG, commercial satellite operators (e.g. SpaceX), hyperscalers with positioning interests (e.g. Amazon/Google), and regional/member-state voices currently under-represented in the network (e.g. Africa).

Two focused tasks, kept separate from each other:

1. Select capabilities and rate maturity. For their product, the group (a) confirms or challenges which capabilities in the model actually apply — the Evidenced / Ratified-pending-evidence / Not applicable three-state idea fits here — and (b) rates current maturity per PPTD dimension for each. Nick raised a possible second pass for target/required maturity; worth offering as a distinct, optional follow-on exercise rather than bundling it into the first ask. This is the part that could genuinely run as an online survey rather than a live session — it's a bounded, per-capability rating task, well suited to async input.
2. Step through the product workflow for validation. Separately, walk the tier-by-tier workflow (§2 of this document) stripped of the principle-level flags and risk scores — just the steps and institutions — and have the group confirm it's accurate: right tiers, right counts, right institutions, anything missing. Nick's own framing for this step: show it as a plain workflow they can "just step through it... yep, that looks right... oh, there's an extra step here." This is a factual/structural check, not a maturity judgment, and shouldn't be conflated with task 1.

What this group does not need to do: engage with Step Criticality, the six-principle rubric, domain averages, or how any of it rolls into a risk score. That's out of scope for them by design — keeps the ask narrow, fast, and repeatable across five products.

5.2 Governance Committee — cross-product, owns the rubric

A smaller, standing body — Nick's own term was "steering group" — that takes the working groups' validated capability lists, maturity ratings, and confirmed workflows as input, and does the harder synthesis on top:

• Aligns and computes each product's results against the six guiding principles.
• Assigns and reconciles Step Criticality per tier.
• Owns the two open methodology questions Nick raised on the 14 Aug call and hasn't yet resolved: whether Step Criticality double-counts against maturity ratings that already factor in criticality, and whether Principle 5 should stay a standalone worst-tier metric or become a composite of the other five.
• Decides what, if anything, goes back to a product working group for re-review versus what the committee resolves itself.

This is also the body that needs full visibility into the underlying mechanism (PPTD math, the domain-average-vs-asserted-departure logic, the Tier Risk Score formula) — the product working groups don't need this exposure, but the governance committee's whole job depends on it.

Sequencing: principles ratification by the governance committee happens once, up front, before any product working group is convened — not per-product, and not something each working group re-litigates. Once the six principles are locked in, working groups run in parallel across the five products; the governance committee's synthesis work happens after each product's inputs land, not concurrently with data collection.

Expect this to take longer than one sitting per product. Building this walkthrough together took Nick and Ben roughly two days, and that was with the framework being actively designed at the same time, not just applied. Even with the survey format reducing live time for task 1, budget generously — splitting a product's workflow-validation session by domain grouping is a reasonable fallback if one sitting proves too dense.