I agree with Mr. Keaton. The bigger question, I think, is about who should be allowed to enter the hallowed halls of show business, where only saintly behavior, following the 10 commandments, and refusing all toxic substances is required to succeed. Yeah, right. Surely IDOL is about finding talent, giving it a chance, and then letting the market determine its future. The audience can decide if someone's sis/mistakes should impact on record sales.
We live in a world of imperfect people, a significant percentage of them -- gasp -- end up as performers (and politicians, but that's another topic). If we suddenly require spotless pasts to simply get up on a stage and wail, look out. (That said, he ain't my idol. But it has zippo to do with his behavior toward significant others...)
"I'm a comedian, but in my spare time, things bother me." Garry Shandling