the worktree pre-warming detail is interesting -- keeping a reserve pool and letting new tasks claim one instantly is the same pattern as connection pool pre-warming in databases. the underlying bottleneck is probably git having to traverse pack files and update the index when you run 'git worktree add'. one thing worth trying if you haven't: sparse checkout on the worktrees can cut that initialization time further, especially in large monorepos where most files are irrelevant to a given agent task.