"How much of what we did was good?" Just about everything. Aside from the extraordinary performances of John Adams's music, which matched Sylvan's voice in uncanny fashion, I cherish the memory of an intensely searching Winterreise at Corpus Christ Church in NYC, in 2001. Condolences to all those who were close to him; he is reputed to have been an exceptionally kind and generous man.
More: Zachary Woolfe in the New York Times, Boston Musical Intelligencer, Lisa Hirsch, Matthew Guerrieri, Juilliard Journal.