The pianist, a noted student of Lennie Tristano, hadn't been in the jazz spotlight for many years. As he says here, he turned down a lot of traveling gigs — with Sarah Vaughan and Stan Getz, among others — to attend to his family, and to teaching and practicing just north of New York City. But his improvisations on record have a certain savory, modern-feeling weirdness to them, and his increasingly rare public performances reportedly sparkled. Some sample recordings are at his website.
Mosca died in 2007, but not before James Lester made this documentary short. This actually appeared in my inbox a while ago, courtesy of today's What Are You Listening To? contributor, trumpeter John McNeil. Apparently, Lester is working on another short on McNeil, which — if you know McNeil's acumen for stage banter — promises to be amusing.