The comments came in, and they were excellent. My readers took time to really think about the story, especially its complicated structure. Where did they fall into the "dream" of the book? Where did they fall out, get distracted or confused? I took all the pages, the emails, and I made a master list. These were the areas to look at more closely. Where I hadn't quite delivered what I wanted.
Of course, with feedback, especially feedback in quantity, there are some rules to keep your sanity. Extreme likes or dislikes are suspect. Opposing views cancel each other out. You look for repeating comments. What many people noticed is often worth your notice.