What the search did to each of the 11 genes across 8 generations. Selection swept trailing_stop through the population: a gene that starts in almost nobody and ends in almost everybody is one the search kept choosing.
The exploration width does not narrow, and that is a choice, not an oversight. Mutation keeps a constant width by default, so the search looks just as widely in the last generation as in the first. Annealing it was measured: it does make the population converge, but on this data a converging search settles for a steadier, smaller champion while the constant-width one stumbles onto the lucky outlier — and the ranking policy says a lucky winner is a winner. Annealing is a lever a competitor can pull (--annealing-rate), not the house setting.
Convergence is not proof. A gene can sweep because every survivor inherited it from one lucky ancestor, not because it is good. That is what the held-out slice and the walk-forward windows are for.