Honestly I think if I had proper cooling nothing would have happened. Also I would never listen to the amp at this level
Instead what could have happened is the clipping occurring at such a loud volume would lead to a fried tweeter or a driver in the speakers instead.
I think your wife could use a quick lesson in audio electronics and electrical theory.
Subject:
"Why one can never turn up a receiver volume to the max".
Simple answer:
One component won't be able to handle it.
Result:
Wife owes husband new equipment.
So perhaps you may skip the talk in the hopes that this would come about, however i don't know too many wives who would actually support the final result as stated.