"Never saw one, but I did qualify my statement by saying that anything is possible. "

Well, I have repaired thousands upon thousands and actually have seen them go that way about a half dozen times. It is not common to say the least.

One weird time I had a connection to the base of a horizontal output, IIRC it was an NAP, and that SOB oscillated on its own ! I am initially looking for a sync problem and it was nothing of the sort. Miller effect on steroids or whatever, I mean how the hell did... ? What's more is it was only a few hundred Hz off, and high not low.

"Yikes. I remember a Hitachi receiver in the shop back in the early 80s that would destroy speakers whenever it wanted to. Play nice, short loud hum, speaker smoke. "

I had a Sansui 8900 do that due to a transistor socket. Blew both woofers in one of the guy's EPIs. I sold him a pair and found out that the polarity of the ones I had were reversed from the original. I mean red to red, black to black, out of phase.