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So it's really pretty >> inconsistent IMO. > > Yes it is going to act in ways that look non-deterministic. And that's > OK, because: > > a) It's not broken. > > b) It's not unreasonable nor even terribly surprising behavior: one > can reason about it. > > c) The requested behavior itself is impossible: "do X for an infinitely > short amount of time". > > Why are we adding code to optimize behavior for callers that should > not even exist? > > thanks, Yerp you convinced me. I also realised that we can't just change `start.elapsed() > timeout_delta` to `start.elapsed() >=3D timeout_delta` because it could end up not waiting enough time (due to integer stuff).