That's okay, Nia! No need to start slapping yourself around.
Well, I didn't mean people I've actually met. I have worked on one of his projects, but just wasn't paying that much attention at the time. I do recall a musician saying Adam could sing anything, but that's about it. I was referring to things I've come across online, like at CB and the Aida board.
I think part of it is backlash - when a performer attracts people who really love him, those who just don't see it start wanting to put him down. And with Adam you have the additional factor which Emcee was talking about a little while ago, the fact that he doesn't put up with snarkiness. I'll bet some Renthead non-fans of his have approached him thinking that their attitude didn't show, but a sensitive person like him would know what they felt and react accordingly. Then they think he's being arrogant.
As far as that certain BWW poster, with him it seems to be professional jealousy by proxy.