What's funny is that U2 have never claimed to be great musicians. It's just that when they get together, magic happens. I think this is what's kept them relatively humble all these years--they know there are better players, but it's the whole of them, the chemistry, that make them the greatest band.
My former guitar teacher, who's a pretty hot session guy in NYC, has a lot of respect for Edge for all the right reasons--it's more than how accomplished the technique is, it's also about heart, soul, and a unique sound, among other things.
About Larry and Adamn--to say Larry and Adam don't work hard at becoming more proficient players is just not true. I've seen so many references to how they're always working at it.
I think the reason U2 are always so quick to give their props to the Ramones and other punk bands is that U2 never would've had a chance without them. You didn't have to be any good with your instruments to be in a punk band, and this gave U2 the confidence to go for it.
I can understand not liking U2's music (well, actually I can't, but in theory I understand that not everybody likes them) so I'm not one for just bitching and moaning about their critics, but some of these guys just sound really jealous.
Ok, I'm preaching to the choir here...