I don't see what was wrong with the Chili Peppers one. It sounded like the real thing.
Saying gibberish, lyrics make no sense, slurred words, humming, making stupid noises, and ... all around dumb.

(bleh. Our local station started playing chili peppers again. Every time I hear that I switch the station to something that is better listening than Chili Peppers - public radio - seriously, I'd rather hear the news about Zimbabwe than hear the Chili Peppers ever again. UGH. )
But oh man, the real bad one was that final countdown one. LMAO! Gah. Not only sounding lame, but doing the lamest song ever.
Couple of em tho ( Nirvana, Foo fighters ones ), if they
didn't sing like those kids who were doing Iron Man they'd have sounded pretty good.