Thelonious Monk was more composer-pianist than pianist-composer, which can also be said of Gerry Mulligan when he laid his saxophone aside (he was presumably influenced by his friend Monk, whom he sounds like on piano on a few nice records I wish I owned). It was a matter of having worked out the music, maybe even incidentally on a piano, rather than having at hand (in the fingers) the sort of pianistic resources which can translate lots of scores recognisably into audible music (if not the composer's idiom or sort of idiom). Monk's early job playing piano for a traveling evangelist (more salubrious than Brahms's Hamburg bar/ brothel) could have been held by a wide range of people; nobody out of immediate earshot had reason to know of qua pianist. When he threw himself into the wider ken in his middle twenties, he was very competent in harmony and the theory that started a legend of academy schooling. It seems his later introversion and tendency to withdraw had its precedent in an intense preoccupation at the heart of all that learning. Self-taught composers have written symphonies well worth performing, but they have not as a rule had careers as performers, much less performers self-taught on their instruments -- and at the same time both working out their musical ideas and trying to work out how to realise them. The major contemporary comparison is between Monk and Clarence Profit, whose contemporaries compared him with Art Tatum (as maybe even better than Tatum!). Profit died too young, leaving a disciple in George Wallington, lots of dispersed influence (maybe on Monk, too) and enough on record to fill one CD: the timing and phrasing are uniquely subtle but the music's more in a conservative but advanced swing idiom that a record company would pay for (and not all of that material was issued at the time). It would have been wonderful if Profit had been recorded live, as Monk was when he'd been engaged by musicians to play piano for the young lions who jammed after hours for the music's sake at Minton's Playhouse.