A skill is real whensomeone else can teach it.

You run the workshop, everyone nods, and three weeks later nobody's changed how they work. The skills that actually stick are the ones peers teach each other — but most teams have no honest way to tell whether that's happening, or whether the whole program only runs because one enthusiast keeps it alive. Teach-it-back makes both visible: did the skill transfer, and is the habit self-sustaining?

Here is the engine's verbatim output on the sample program. Sixty percent of sessions were SOLID — on density alone that's SELF-SUSTAINING. But the last two meetings both went HOLLOW, so the keystone gate fires and the program reads DORMANT. A program that was working but has gone quiet is dormant, not self-sustaining.

TIB-079  Teach-It-Back AI Champion Kit
============================================================
  Wk1 Prompt basics      Dana       acc5 tr4 pp4  ->  80  SOLID
  Wk2 Verifying output   Marcus     acc4 tr4 pp5  ->  80  SOLID
  Wk3 Building a Project Priya      acc5 tr5 pp4  ->  80  SOLID
  Wk4 Data analysis      Dana       acc2 tr3 pp1  ->  20  HOLLOW
  Wk5 SOP writing        Sam        acc1 tr2 pp2  ->  20  HOLLOW
------------------------------------------------------------
  Sessions: 5   SOLID: 3   solid-share: 0.6
  Base band: SELF-SUSTAINING
  KEYSTONE GATE FIRED: last sessions HOLLOW
  PROGRAM VERDICT: DORMANT
  Fix focus: Wk4 Data analysis / independence