When I first got into building models I did research on spray painting and learned the "place the can in warm water" technique. I did this using testors/model masters a few times with warm water - not hot - and one can "bubbled" on the bottom. What I mean is that the bottom of the can which is concaved upward concaved downward to the point that it won't stand up now, I have to lay it on its side. It looks like it came close to bursting. This really surprised me as I was only using warm water, not hot at all.
I'm not trying to contradict what you're saying, Gimme Shelter, I am still a novice. I'm also not sure it was near bursting. It just alarmed me enough that I no longer use warm water.
Again, I'm not trying to say Gimme Shelter is incorrect in any way, just looking for info as to if I did nearly rupture a can.