Many thanks to Chinhodado and the poster who narrowed it down to KB2778344 (I can't see who at the moment), as well as all the other participants. In addition to a couple random times, I received the gift of the BSOD in the middle of compressing my SSD
- twice. Not pleasant. Removing the update fixed it, and though I'm pretty good with computers, I don't know if I would have thought of this - Cheers!
I resist throwing dung on the heap, but there should at least be an official knowledge base response somewhere that says like "hey, there was a security threat so we put out this update, but it may conflict with some 3rd party SW", or some such. I suspect testing was inadequate, and perhaps policies should be revisited. Timeliness vs well-tested often creates compromise.
Power to the People!