Why we pivoted then
F11.5, the one item reopened in F11, is blocked by cost without a run. F8 comes next in the ranking but has no open item, so the next family with work is F5 (tenth), with F5.3. The ranking is unchanged.
What happened before
- F11.5, the poem code as SOE agents used it: two picks of five words from anywhere in K1-K3 make 8.1 x 10^17 key pairs. The known letters cannot be placed without both whole keys, so no constraint search cuts the space, and enumerating it is out of reach. A single-pass version would run, but would not test the agents' method.