I know PERSONAL EXPERIENCE MEANS NOTHING, but I'm a pretty mediocre player with no real life experience, and no actual non-computer experience in other fighting games, and I've done pretty alright for myself with Carl online without being able to do the clap loop even close to consistently. I try to set it up, but usually I don't get more than one throw in, or I just go into Nirvana's uppercut thing.
Maybe it's just because everybody online sucks, but I have beaten people ranked in the top 10 for several characters. If he's really that bad, I must be better than I thought.