There's a fairly interesting article about Bono's evolution in the Sunday Herald online. For our purposes, here's the money quote:
"Bono had re-invented himself as an identikit rock star: 'I had Elvis Presley’s leather jacket, Jim Morrison’s leather pants, Lou Reed’s fly shades, Jerry Lee Lewis’s boots, Gene Vincent’s limp.'"
This is, of course, referring to the time when Bono was flirting with Advancement. I don't think he quite got there because there was still a layer of irony in his act, but it was a great try. The article is by someone who has known Bono for a long time, so he seems to have some insight, though you always have to be suspicious of journalists who say they are friends with rock stars, even if they have known them for a long time.