Here's the setting: I am syncing my entire books library on my MacBook with my iPad. On my Mac, there are 122 books (both .epub and.pdf). I also use iTunes U on my MacBook, and some of the courses I download have .pdf slides in addition to videos. However, I am not syncing iTunes U courses on my MacBook with my iPad.
And here's the issue: somehow, all the course slides from iTunes U appear in my books library on the iPad. That is, my books library on the iPad now contains 129 books, and the number is growing with every slide set that I download. So these slides appear in iBooks, but not in my books library on my MacBook. In short, I say sync all books, and it laughs into my face by syncing to different numbers.
How do I turn this feature off? Is it some setting that I've missed, a weird feature, or an annoying bug?