We picked up his option 2/3 of a season ago, at the deadline for picking up that option. And it was a cheap option at $2.4M. He was a developing player. You hold on to those guys until you find a reason to get rid of them. Apparently we decided that, given the option of having $15+M more in our pockets, or Papa, we went with the $$$. I don't think you're going to find a team that is going to think the opposite - i.e. sign Papa to a contract worth $15M. Would we rather have $2.4M or Papa? Hey, you take your chances. But when the question is $15M or Papa, it's a different story.
Now, I'm not sure I do the entire trade in the first place, because I think over the summer Hill could fetch more than a second rounder. Plus, I didn't see the urgency of getting rid of him, considering we just gave him his money over the summer. But once that trade is decided on, cutting Papa (or Malachi) is the move you HAVE to do, and you don't look back at the completely-NBA-standard-in-almost-every-case pick-up of that year three option and use it as an excuse not to waive him.