Yes, this could be it. Here's how my actions match your steps:
1) You change the filename of a file or rip a new file
Yes, but in my case via ripping a new CD, not by me changing any filename manually. So the file names of the rip are determined by the naming expression specified in MC.
Except... Maybe I have also experienced it with a manual edit when I attempt to recover from the bug. When it hits and I try to fix the track by manually editing the Filename, often I can't. When I finish typing, MC will revert the File name value back to the prior "wrong" value -- perhaps because there wasn't enough time elapsed. When I do my "reliable" fix -- go to the drive, find the file and copy+paste the path+filename into the Filename field -- that requires a minute or two which might be enough time for MC to have written the pending change so it accepts my edit.
2) You change no other filenames for a minute or two
Yes, because I do nothing to filenames except at the end when I run Rename/Move. Otherwise,the only Filename changes are done by MC when it assigns names during ripping, or when the bug kicks in. The only manual Filename field editing I ever do is to try and recover from what the bug does.
In case it matters. I rarely finish a CD rip (so maybe 10 to 20 tracks) then immeidately start working with it. Sometimes I won't touch the tracks for hours or even a day, either because I continue to rip CDs so I have large batch to work with (efficient for my tagging process) or because I can be ripping while doing other things nearby, but then need to sit down and focus on MC to do all the tagging.
3) You edit the name field of that same file
Yes, this is what triggers the bug. The above explanation of steps and timing applies to many tracks as they accumulate in Recently Ripped, waiting for me to tag them, and there are three main reasons to then edit a Name field:
Often only one track needs its Name edited, usually to correct a typo.
OR, several or even all tracks on a ripped CD will need the Name edited because I don't like what YADB gave me, and I can do so without trouble. Typically I would do this quickly, blasting down the list, editing fast and moving to the next track -- and no bug.
OR, I edit most or all the track Name fields, but only ONE triggers the bug -- but I've long sensed that there's a timing element to the bug, that it only happens after a "pause" in my work (which is why I commented on my typing speed). It's almost like the bug happens after I think all the tracks are OK, so I've definitely paused for a minute or two or several, then I spot one bad Name, and edit it -- and I recall a dread that "I hope this doesn't trigger the bug" and sometimes, it does!
So yes, the pattern you describe does match my experience.
And while the bug can happen again in a ripping/tagging session, it's usually not for several minutes or after working through several more tracks or after ripping another CD.