I hate to say it but OP is right. My first phone became unresponsive too 5 times and nothing worked. Took me 20 minutes fiddling with power and soft reset buttons to bring it back to life so please don't assume user error here.
I am not defending OP nor do I agree with him but I experienced the same thing. My replacement L920 on the other hand is flawless
knock on wood buddy. my 2nd 920 was flawless until last night.
you were lucky. your phone eventually responded to the reset. mine didn't work. me and the att rep was on the phone for a good 20 mins performing the reset procedure and nothing.