openai/gpt-chat-latest → A (9:2)

Side A substantially redesigns pair selection by removing the generic priority/sort-key machinery, avoiding repeated rank-centrality work until the pool is fully connected, and splitting the logic into targeted growth and adjacent-rank zip passes. Side B is an incremental improvement on top of that design, adding randomized endpoint selection from the largest established component to reduce deterministic attachment bias, but it does not change the core algorithm as significantly.