The worktree approach is interesting - keeps the filesystem separation clean. The parallelism tradeoff makes sense if the tasks are truly independent, which in practice is most of the time anyway.

What does your spec file look like when you kick off a new agent? Curious if you start from scratch each time or carry over context from previous sessions on the same project.

I describe this in the article - I mostly kick off a new agent per spec both for Planners and Workers. I do tend to run /fd-explore before I start work on a given spec to give the agent context of the codebase and recent previous work