There is no one at 145 or 155 on this planet that can beat BJ at 155. It's just not going to happen.
BJ's true test lies at 170. I think he needs to step up, but not put on a bunch of excess weight. He is probably right at 170 come fight time now and that is what he should stay at for 170.
Give him Alves, Fitch or Kos and see how he does. I am fairly certain he will beat all three of them. You have to think, the only time BJ has ever lost, aside from Pulver in 2002, is against much bigger fighters.. Hughes, GSP and Machida. He's beaten Hughes once, went to a decision with our current LHW champion, went to decision with GSP in a close fight the first time, and got outclassed by GSP the second time.
You absolutely can't knock the guy at 170 considering he's only fought the best there. Hughes was in his prime at the time and so was GSP.
BJ is the best in the world at 155 and given a couple years at 170, instead of jumping up to fight the champ who has cleaned out the division, he could have easily cleaned out most of 170.