"Hindsight is 20/20" -- yes, but you never really have the true counterfactual.
Birdman is playing great, and I wish all the best for him (and I hope Denver moves on past Dallas, as looks likely), and I wish that Birdman was playing for the Cs instead of Denver.
Given all that, it is still not clear that he would have had as much success in Boston as he is having in Denver. He is a drug addict - recovering, yes, and all the power to him - but he is a drug addict, and things could have gone very different for him this year if he was with the Cs, living in Boston away from his support group, etc.
Not trying to knock the guy (see para. 2 above), just trying to throw an alternative view out there...