ER, there's a nice article about Pink floyd in the new Rolling stone I think you'd like,
http://www.rollingstone.com/music/news/surviving-members-of-pink-floyd-revisit-dark-side-band-tensions-20110928
The link doesn't take you to the full article, you'll have to pick up a hardcopy for that, but it does give some teasers. Read the whole thing today and found it a very interesting insight to the dynamic of the band. I knew of the tensions in the band during their greatest productive period; this provided more of the story.
It seems a little tension is good for a band, but too much, or for too long, and the whole thing falls apart.