Thanks for the answer! What you’re saying seems to be true, but it wasn’t given in the instructions, so I guess you were supposed to figure out that this was the case. It seems this was true for everyone, so it wasn’t just me that got lucky. I got confused by my assertion failing on the example, because the second path reaches the goal in three steps which is not a multiple of the instruction length (2). This never happens with the real data. The example wraps around neatly at 6 instead, so just removing the assertion makes my code work on the example too.

I use it from time to time. Often I test manually instead of automatic, and it often works very well.

But if you want a story about an unconventional use of git bisect, I think there’s one about the time I had a directory with lots of files, and one of those files was causing some problem, but I didn’t know which one it was. Those files were not under version control, but I created a repo with them, where each file was added in a separate commit. Then I could use git bisect to find which file was causing the problems.