^ I have no idea about other bands because, honestly, I don't follow other bands so much. Other bands may either have more musicians that can produce these sounds or they don't have these complex sounds as U2 have or they don't care and play half playback and sequence stuff in. Honestly, I was never irritated when I found out about Terry playing backstage, I always thought it was funny and better than having pre-taped stuff. I'm sure there are other bands who do that as well but I'd have to go to other bands' fan boards where people are dissecting their live shows as much as some U2 fans are on this board.
I don't care. U2 are a great live band, they play live, and if there is a sound they cannot produce on their own because they are just 4 guys on stage, I don't care where that sound comes from. If they come out on stage and put on the best show they can, if they have fun doing it and if the audience has a great time, I couldn't care less about what's going on backstage. I don't go to a U2 concert to dissect every little thing. In fact, I'm sometiimes glad Bono is forgetting lyrics or Edge is making mistakes, because it shows they are human and far from perfect. I'm enjoying the shows for the music and the atmosphere, and I think U2 are one of the best live bands on this planet. Otherwise I wouldn't bother going to all these concerts this summer.
Oh, and I'm sure Terry can live with his role very well. In fact, he was on stage a couple of times and Bono introduced him to the audience. I wouldn't mind to see him on stage more, but if they decide it's better this way, fine. It's not as if the band comes up on stage and says: Well, of course we're doing all this on our own, no pre-taped sounds, no other musicians. See, we can produce all these sounds ourselves. I wouldn't say they are cheating. If Bono lip synched, not THAT would be cheating, I'd be pissed, but we all know he doesn't (and, in fact, he hates it).