A Keith Richard fan, he played guitar in a London rock musical called
Mother Earth with his friend, keyboardist and arranger Richard Hartley,
in the early 70s. Hartley asked him to sing backing vocals on the song
demo tape for Richard O'Brien's musical play The Rocky Horror Show in
1973. Blair played guitar in the original four-piece stage band at the
Theatre Upstairs, played on the London cast album, and was asked to
play lead guitar on the soundtrack sessions for The Rocky Horror
Picture Show (with Procol Harum's Mick Grabham on rhythm guitar).