Or, you know, both. Why not leave a comment explaining why a non-obvious code block was written. It's not an either-or situation. I've left a before because of

Or, you know, both. Why not leave a comment explaining why a non-obvious code block was written. It's not an either-or situation. I've left a before because of a subtle GC bug triggered only on particular hardware, which could not be replicated in the development environment, and would only be revealed by a particular coincidence in timings. How do you test that?