Festival when he gave lengthy in-between-song speeches on several controversial subjects, including the JFK assassination and the benefits of giving LSD to "all the statesmen and politicians in the world". He further irritated his bandmates at Monterey by performing with rival group Buffalo Springfield, filling in for ex-member Neil Young. His stock within the band deteriorated still further following the commercial failure of his song "Lady Friend", when it was released as the A-side of a Byrds single in July 1967. His absence from many of the recording sessions for The Notorious Byrd Brothers was the final straw for McGuinn and Hillman. Crosby received a generous severance package and began to collaborate with his new musical partner, Stephen Stills. It has been suggested that the horse on the cover of the album was unkindly intended to represent Crosby, although this has been denied by both McGuinn and Hillman. Much to Crosby's chagrin, McGuinn and Hillman reworked his unfinished song "Draft Morning" following his departure and included it in the final running order for the album, giving themselves a co-writing credit. Crosby ended up playing on around half of The Notorious Byrd Brothers: on his own three songs, along with "Change Is Now" and "Old John Robertson". He also appears on several bonus tracks on the 1997 reissue, including "Triad", "Universal Mind Decoder" and an early version of "Goin' Back". Gene Clark's return Following Crosby's departure, Gene Clark was asked to rejoin the band. Clark had originally left the Byrds in early 1966 due to his fear of flying and his tendency towards anxiety and paranoia. His debut solo album (co-produced by the Byrds' then current producer, Gary Usher, with both Clarke and Hillman playing on it) had been a critical success, but a commercial failure and Clark was currently inactive. Clark rejoined the Byrds in October 1967 for three weeks, during which time he and the band performed on The Smothers Brothers Comedy Hour television program, lip-syncing "Goin' Back" and "Mr. Spaceman". The Byrds also played several live dates with Clark during a tour of the Midwest. Following the final concert of the tour, Clark's fear of flying again became a problem when it prevented him from taking a flight to New York with his bandmates and, as a result, he left the band soon after. It has been debated by biographers and band historians just how involved Clark was