Crosby, Stills and Nash first played together in 1968, but it was nearly a decade before they toured as a trio. That's because a certain shaggy Canadian fellow joined their ranks right before they hit the road to support their debut LP. They sold millions of records without the guy, his contributions to their second record would be a scant two-and-a-half songs (only one of which is truly great) and, as Stephen Stills certainly learned during his time in Buffalo Springfield, he was an incredibly destabilizing force almost completely incapable of operating within the confines of a democratic group.
To be fair, rampant drug use and inflated egos on all sides were largely responsible for CSNY's implosion in the summer of 1970. When they returned in 1974 for a stadium tour fueled by premature nostalgia for the 1960s, those problems returned worse than ever. A planned reunion album was scrapped and when the other guy cut an LP with Stills in 1976 and hit the road to support it as a duo. David Crosby and Graham Nash were understandably enraged, but they got their revenge when the other guy bailed on Stills midway through the tour with one of the most infamous telegrams in rock history: "Dear Stephen, funny how some things that start spontaneously end that way. Eat a peach."
This put Stephen Stills in a very, very awkward situation. His former CSN partners were on the road doing just fine as a duo and his Buffalo Springfield buddy was already prepping to hit the road with Crazy Horse. He was a man without a band, so he went backstage at a 1976 Crosby and Nash gig in Los Angeles and pleaded for forgiveness. Realizing that Crosby, Stills and Nash was a much more potent formula than Crosby and Nash, they let him back into the fold and began plotting their first album as a trio since the 1969 debut.
CSN hit shelves on June 17th, 1977. It was the absolute pinnacle of the punk movement and the cover photo of the trio lazily lounging on a yacht was as far away from the grimy world of the Sex Pistols as possible, but good songs trump everything and the album was packed with them. New tunes like "Dark Star," "Cathedral" and "Just a Song Before I Go" helped the album reach Number Two on the Billboard 200 and ultimately outsold their debut. They supported it with a huge American arena tour, finally proving they could play the big halls without that other guy.
Here's video of them performing "Just a Song Before I Go" at the Summit in Houston in 1977. The venue was one of the first in the country to utilize video screens and they kept tapes of many of the acts that came through. That allowed Bruce Springsteen to include footage of his Houston performance from the following year on his Darkness on the Edge of Town box set and it allowed for this CSN clip to hit YouTube. For some reason, it's followed by the group playing "Dark Star" on the Daylight Again tour in 1982. Against all odds, that was yet another big album thanks to the hits "Wasted on the Way" and "Southern Cross." But it was their last gasp of relevancy before David Crosby's drug problems and imprisonment hobbled their momentum.
They carried on as an oldies act once Croz was let out of a Texas state prison and even teamed up with the other guy for big money tours in 2000, 2002 and 2006, but they got into a huge fight in 2015 and broke up the group. David Crosby and Graham Nash are no longer on speaking terms. This year marks the 50th anniversary of their formation and next year will mark the 50th anniversary of their first album. A reunion tour would mint money, but right now there's no sign that's on the horizon. That said, huge payouts have a way of making people forgive each other. If the offer is big enough, the other guy might even get involved.