here is the exact quote from the book:
"U2 ARE JAMMING again, coming up with enough songs to insure boxed sets for years after their plane crashes. Watching them work this way, it is really striking how much of the U2 sound frequently credited to Edge alone depends on Adam and Larry. Adam often plays with the swollen, vibrating bottom sound of a Jamaican dub bassist, covering the most sonic space with the smallest number of notes. Larry, who taught himself to drum and consequently got some things technically wrong, plays with a martial rigidity but uses his kit in a way a properly trained drummer would not. He has tom-toms on either side of him, and has a habit of coming off the snare onto them that is contrary to how most percussionists use those drums. We're not talking about huge technical innovations here; we're talking about personal idiosyncrasies that have over fifteen years solidified into a big part of what makes U2 always sound like U2, no matter what style of music they are playing. It is also why bands that imitate U2 never get it right, and why all the guitarists who try to play like Edge end up sounding so lame; their rhythm section never sounds like Adam and Larry.
The great joke is that Adam's and Larry's playing so perfectly reflects their personalities. Larry is right on top of the beat, a bit ahead—as you'd expect from a man who's so ordered and punctual in his life. Adam plays a little behind the beat, waiting till the last moment to slip in, which fits Adam's casual, don't-sweat-it personality. [. . .] They've played together so long that they seem to spread the beat out between them.And they create a blanket on which Edge's chord layers rest."
^_________________^ you should read this book ;]