Yeah, Don Schlitten was doing outstanding work back then. And not only with Xanadu. Between the sessions that he produced for Cobblestone, Muse, MPS, and Xanadu, his productions crop up again and again on my survey.
Certainly, Schlitten is one of the most important jazz producers of the 1970s -- right up there with names like Nessa, Eicher, Cuscuna, Keepnews, Michel, Porter, Winckelmann & Weber, et al.