Several times more? That would mean my friend's rig should be dead as he uses a 100 watt jcm800 with a 50w cab. Even for rehearsals and live. Guess what, after more than ten years he has it, nothing happened.
That's because he's only using half the amps power at most. And the difference in power between a 100w head and a 50w cab is a drop in the ocean compared to the same amp with a set of headphones that can only handle a fraction of 1 watt before blowing up. In such a situation, peak power even with a tiny fraction of the power from the amp being used can still definitely bow the headphones.
I'll close this thread now. If you blow the amp because you don't understand the importance of matching the wattage of the amp to the cabinet then you cannot say you were not warned.