Before the playoffs last year, people had no idea who Pierce was.  I can't tell you how many people outside the east were shocked at how good of a player he was.  My point is that people don't know about the Celtics history of the last few years and why Doc had a tough time when he first came in.  
I pretty much agree.  Any fan of the game had probably heard his name, but because Boston went through a long rebuilding period, they didn't get any prime time coverage.  I had no idea how good Pierce was till I watched him in last year's playoffs.  (Can say the same thing about Bosh, Roy, and other very good players who don't get much coverage.)
I also don't think people should underestimate the value of a good coach.  Phil Jackson came in and took pretty much the same Laker team that couldn't advance in the playoffs and won a championship the next year.  You need more than good players to have a good team.  
Really hard to argue that Rivers is anything other than a good coach when he has a ring.  I think he does a very good job.