I had conflicting answers to that.. some say that it just makes the amp work harder creating the warm overdrive tone and the amp was probably designed for 4 ohm anyways even though everything I read said it is only 8 ohms...

Others respond like you did saying I will fry the amp...eventually

I played the whole show Saturday night without any problems..I did notice that near the end of the set.. the amp would loose a bit of volume and seemed to be more overdriven than when the amp came off stand by...