Yeah, I assume the part of the kernel used would affect how much of it comes out the other end- ground whole kernel corn being the least digestible? I'm not sure, we haven't gotten to specifics yet.
I don't know about diverticulitis- my roommate in college had ulceritive colitis, and she wasn't able to eat things like apple skins. I think in her case, the skins just made her system work to hard to digest them, so it caused irritation and inflammation.
The Intro Nutrition (the one I'm in right now) and Small Animal Nutrition courses are both required, and the Advanced Small Animal Nutrition course is an elective. Hill's doesn't give any seminars during the courses- we are taught by university faculty, just like all our other courses. Hill's does sponsor lunchtime seminars which are fully disclosed to be sponsored by them, and they do bribe us there with pizza, subs, etc. So does Iams, and Purina, and Banfield, and Fort Dodge, and lots of other companies who could potentially make money off of vets. Don't worry, we are very skeptical and go in fully aware that they are just commercials. ;-) We are poor and will take all the free food we can get!
I'll admit, Hill's did purchase us each a copy of our Small Animal Clinical Nutrition textbook, which is awesome because I really didn't want to spend another $100 on yet another textbook...
But in case you're wondering, my puppy eats Eagle Pack!