closure-by-lag
Drawn at its defaults, in the rows the exchange set aside. It takes no options at all, so every essay calling it gets this exact drawing.
Called by 4 essays
the blast radius of changing it
A cycle sums to a whole turn
The test proposed for whether three displaced chains are a three-cycle was that their displacements sum to zero. Three chains rotating into one another's places each move about a third of a turn the same way round, and a third of a turn three times is a whole turn โ which the unfolded test calls the worst row in the census.
What a plant might be doingThe lag decides whether it closes
Seven of the thirteen excluded rows have displacements that cancel and six do not. Every row that closes kept a lag of seven or eight and every row that does not kept four or five, thirteen times out of thirteen โ and then a lattice nobody had cut broke it.
What a plant might be doingThe rows nobody added up
Seventeen of the census's thirty wrecked cuts come back as one balanced pair of displaced chains, and every claim about the exchange is quantified over those seventeen. The other thirteen were set aside as having three or more exceptions and never looked at again. They are one addition each.
Stems and conesA fifth cluster
A correction to the exchange's size was fitted over four hop clusters and its own file said so. A search turned up a fifth, at a hop smaller than any of the four, and the rule is right on it โ which is what a prediction being confirmed looks like when the confirmation is worth having.