The only thing is that in big time regular season games and certainly in the playoffs, there isn't going to be a "second unit." Doc is going to keep at least a couple of starters on the court at all times. That means that the C's will likely be able to get by with just House, Daniels, Wallace, and maybe for a few minutes Davis. Thus, Allen isn't going to play when it matters.
So if Allen is part of a "second unit" that gets in against the likes of the Nets and Clippers, I'm fine with that. Though I agree with you that I never want to see him play in a meaningful game again.