I'd never heard of him either, or if I had, he didn't stick in my head as a name I'd remember later. But then that's only fair: he doesn't know anything about me. ;-)
It doesn't do any harm to have other luminaries promote your work...
I love Haas too, and bought his book Color Correction and wish I had not. For some reasonn it felt cold, and representative of lost intention. Which is not how I had previously felt about him at all. No, I honestly can't really tell why the change. I ended up wishing it had all been his black/white stuff with Marilyn and the rest of them on the movie sets.
Perhaps it is down to Leiter, who managed to cover the streets with a soul so missing from Haas's clinical, overlyn crips colours. I'd often wondered why Haas had been neglected by the photo-art establishment for so long, with the put-down that he was too commercial; I think I have worked it out for myself, decades behind them.