I think he signed because he loves the franchise, his players and as someone else said,because it's a boat load of money that will set him up for the rest of his life.
However, I also buy into the OP's suggestion that there may be some things we don't know about as far as possible future players coming here.
We'll see if Dwight re-signs with the Magic. If he doesn't, I wouldn't be suprised to him land in Boston.
Doc is loyal but he also wants to win. I think there are two possibilities re the future of the team and the players:
1. There may be knowledge of guys who want to come here, like Howard, or
2. The management has said they will pay the price to build a winner and Doc has confidence in that.
Let's be honest though, with Rondo, Green, Pierce, DWest and Bradley as a young core, you are one big signing and a few small signings or trades away from being very competitive.
So I'm not so sure that Danny, Doc, Wyx and team see a drastic decline and a major rebuilding process on the immediate horizon.
I mean, if you could:
1. Sign Aaron Gray
2. Trade Baby, a re-signed Krstic and a 1st for a good young off guard - JR Smith?
3. Draft a good young athletic PF
4. Sign another good, vet PF with your mid level( Carl Landry?...
We are in contention next year, big time.
A. Gray / Krstic / Shaq / Erden
KG / Carl Landry / Rookie
Pierce / Green
JR Smith / Ray / Wafer
Rondo / DWest / Bradley