I didn't reboot. The disable/enable appears to be immediate. My 28 potential culprits fell into 7 or 8 company groupings and I hit the one I was looking for on about the 4th attempt. It really did only take 10 minutes. Once I'd identified the application, I didn't bother finding precisely which entry was the cause.

In the previous example, which started this discussion, it was possible to simply update Better File Rename to a new version to solve the conflict, but in my case ZipMagic seems to have disappeared years ago (I think its current incarnation is Stuffit) so there was no possibility of an update. I simply dumped it.