Facilitator by default, thinker optionally

The rule. Every abcd surface — a verb's output, an intent, a validator's verdict, a generated report — addresses the technical facilitator by default: the person orchestrating the work, who needs precise, mechanical, actionable structure (what changed, where it lives, what it touches, what to do next). The product thinker is served by an optional, additive layer on the same artefact: the working-backwards "why it matters", the outcome framing. The default reading is facilitator-complete; the thinker layer is a lens you switch on, never a prerequisite for using the surface.

Why. abcd already lives this split without naming it — intents are press-releases (thinker-shaped) while the operating surface is verbs (facilitator-shaped) — so naming it makes the split deliberate and checkable. The stance is the established SOTA for dual-audience information design, not a local invention: progressive disclosure (NN/g — lead with what the immediate user needs, defer the rest to a second layer), Diátaxis (this repo's own docs convention — separate audiences/needs into distinct modes rather than one blurred page), and the journalistic inverted pyramid (the actionable core first, elaboration after). A surface that speaks only product-thinker (vague outcomes, no mechanics) strands the facilitator who has to act; one that speaks only mechanics with no available "why" strands the thinker who has to decide whether it matters. The default must be the layer that lets work proceed — the facilitator — with the thinker layer one switch away.

Bounds.

• The default layer is mechanically complete on its own: a facilitator never needs the thinker layer to take the next action.
• The thinker layer is additive and clearly delimited (a section, a --why lens, a flag) — never interleaved so that the mechanics turn vague.
• Applies to generated surfaces too: a validator or report leads with the facilitator structure (the routing table, the interdependency list); the press-release framing is the optional layer, not the headline.

Promotion. Unenforced today (principle rung). Promotes to a discipline when a surface-lint can check that a user-facing surface carries a facilitator-complete default and an optional (not mandatory, not absent) thinker layer — a neighbour to ../intents/disciplines/itd-79-persona-registry.md.