• ✓The named technique is anchoring — find the first and the last, then squeeze inwards on what is left
• ✓The shuffle is proved never to hand over a board already solved or nearly solved (npm run verify:teenfive)
• ✓A wrong board hands back ONE pair that is the wrong way round, never a cross over the whole thing
• ✓The Kidsquare Rule: three checks in and still tangled hands over both anchors — six steps still remain to reason about
• ✓Six processes that each have a physical reason for their order rather than a sequence to memorise: rain, a seed, bread, a message across the sea, a law, a song

✓ = done · ☐ = planned. Every game is built one step at a time like this.