The worktree part is the easy half. Running parallel Claude Code subagents, the bottleneck is never "can they run without stomping each other's files." That's solved the moment each one has its own checkout.

The hard problem is architectural consistency. Agent A renames a type to X. Agent B, in a different worktree, independently renames the same type to Y because neither saw the other's decision. When you merge, neither worktree is "wrong" but the code is incoherent. You need either a shared decision log that every agent reads before starting, or an orchestrator that hands out scope narrow enough that no two agents can collide.

Zed's post is solving filesystem-level parallelism. The harder coordination problem is semantic, and that's where time savings from parallelization go to die.