Crosby, Stills & Nash were already a supergroup -- and one with a hit album to to their credit, no less -- when Neil Young joined in the summer of 1969. And even though he brought the band even more star power, not to mention his distinctive voice, guitar, and songwriting skills, he also added a volatile new ingredient to what was already a somewhat unstable blend of egos. As Graham Nash puts it in the most recent edition of Mojo: "A lot of people say, 'Was it great that Neil Young joined CSN or did that kill CSN?'"

It's a question whose answer probably depends on your personal favorite albums from the frequently shifting configurations of the quartet, but there's no getting around their propensity for butting heads; Nash joked that adding Young was "was like lobbing a hand grenade in a vacuum," and the article points out that before Young came on board, Stephen Stills tried to convince Eric Clapton, Steve Winwood, and George Harrison to be their fourth member.

"We could have gotten anybody and we wouldn’t have had to give them a fourth of it," joked David Crosby, although he also allowed that their infamous disagreements and implosions would have happened no matter who else was involved: "If you give a bunch of very young guys millions of dollars and get them high as kites and let them loose, it’s just sort of inevitable."

Just as inevitable, added Nash, was the thing that kept on -- and keeps on -- fueling their creative bond. "What draws this band and what pushes it apart has the same answer," he pointed out. "The music."