That book is worth reading. The frustrating part of the book for me was, since most of his music hasn't been recorded, you read about pieces you'll probably never hear. And he writes in such a way that it doesn't look or translate to a keyboard as good as it does when it's actually sung.I'd quite like to get ahold of Rob Wegman's biography of him some time.
But I'm glad for what's out there. And if you ever find a recording of his Missa Fortuna Desperata, please drop me a line.