The gap between what I think I understand after reading the text and what I find I really understand when I hit problem 1-2 in each section is immense, so I'm going to stick with the problem sets.
You can just ROT13 the answers you don't want to make public.
Just think of how much harder you made college for yourself.
Edit: to be serious, the solutions at the back (which I look forward to flipping to after every other exercise, kind of like a rat getting a food pellet in an experiment) are interesting in their own right. He plants little clues in there, to hint at what was important or why he asked the question.
Yes, ROT13 (or maybe ROT47) might be enough to stymie lazy solution-seekers. Might do that here if an even-numbered exercise seems to warrant some discussion.
I just noticed that odd exercises helpfully have solutions in the back. So moving forward, I'm planning to do all exercises marked recommended/important, all numbered 1 mod 4, and a few others that seem helpful.
For the exercises which don't have solutions, it would be nice to have a place where we can compare answers yet not post them to the public internet. Would anyone else find that useful?