Of course I can tell the difference between Limp Bizkit and 311. My point is very simple: when rock bands rap, it is largely bad. I see it as a fad that was appealing during the late 90's, but most of them do it in a way that comes off pathetic and contrived. There are very few rock bands that I would say can pass the "rap credibility" test.
Yes I get it about the Beastie Boys. Lots of music groups start out one way then evolve into totally other things, and as long as the music is good then it is good. Duh.