For me: Will this task take 30 seconds or 3 minutes. With good planning I've been able to step away and come back. Sometimes it decides to prompt me within 5 seconds for permissions. Sometimes it runs for 15 minutes.

The output is still small and I can review it. I can switch tasks, however if it's my primary effort for the day I don't like stepping away for an hour to do something else.

Not the OP, but the new LLMs together with harnesses (OpenCode in my case) can handle larger scopes of work - so the workflow moves away from pair programming (single-file changes, small scope diffs) to full-feature PR reviewing.