He had a reputation for going his own way -- some say he was never exactly a bebopper -- but he worked steadily, and was recorded in 1944 with Coleman Hawkins and 1946 with Dizzy Gillespie, all not released till later.
It's hard to say, from this perspective of time, how much of Monk's reputation was still underground. It's hard to imagine him as ever having been anything but a towering figure. But it wasn't until 1958 that he won a DownBeat critics' poll, and Oscar Peterson totally dominated the readers' poll throughout that era. Why didn't Alfred Lion release any of those sessions that Monk cut for Blue Note until nearly a decade later? He was at least as hip as Bob Weinstock -- hip enough to bring Monk into the studio. But he must have surmised, and probably correctly, that there was no demand at all for Thelonious Monk records in 1947.
I can find nothing on Gerry Mapp other than his presence on two sessions with Monk, and this never seems right to me. A guy that was good enough to be tapped for a recording session with Monk - there ought to be more about him.
Art Blakey is another story. By 1954, he would form the Jazz Messengers, and become one of the greatest bandleaders in the history of modern jazz, and a star of the Blue Note stable. In 1952, he was still one of the two go-to guys for every recording Bob Weinstock could get him on. Blakey, Max Roach and Kenny Clarke were the pioneers of bebop drumming, and it was Blakey and Roach for Prestige. Max Roach was to describe Blakey years later, in a eulogy:
Art was an original. He's the only drummer whose time I recognize immediately. And his signature style was amazing; we used to call him 'Thunder.' When I first met him on 52d Street in 1944, he already had the polyrhythmic thing down. Art was the perhaps the best at maintaining independence with all four limbs. He was doing it before anybody was. And he was a great man, which influenced everybody around him.Monk went on to become recognized and recorded widely. Monk's Dream was the title track for his first album for Columbia. Bye-Ya and Little Rootie Tootie have become jazz standards. It's a thrill for me as a jazz lover to hear them in this chronological context, in their first recorded versions.