Well the point was I don't know I want to reference back to something until I encounter something new. Good writing isn't all foreboding. So a depiction or conversation may seem innocuous but become much more relevant 70 pages down the line. I'm not good enough to predict those situations, but have strong enough recollection to want to go back and review the older passage.

Agreed, the same goes for reference books. In a paper book, I'll often find things that I didn't realise were important at the time, or a later conversation will bring to mind, and I'll recall something fuzzy like: "It was in the lower half of the right-hand page, a few pages after that diagram with the donkey in it", but can't recall anything that will allow hard searches.

I think this is a technology issue-skipping back pages or searching is difficult with today's e-book readers, but I can easily see it becoming easier with e-books than with paperback books in the future. As with many technological advances, I imagine it'll take more initial effort to learn how to efficiently read the way you want with e-books, but once you do it'll be significantly faster.

In other words, someone needs to develop what Vim/Emacs is to text editors, for e-book readers.

I guess, but the behavior I have with books wasn't learned (outside of the obvious in learning to read, use a ToC, look up an index, etc.). Flipping back to a previous section is just a natural behavior -- it's flipping through a stack of anything. There's no analog in ebook devices. Perhaps there could be one, but it'd have to be a learned behavior, not a natural one, and thus will always feel unnatural.

Personally I don't think learned behaviors have to be unnatural. Writing and driving are learned behaviors which feel completely natural to a lot of people.

In fact, writing is an interesting example because many people say that they can think perfectly while writing by hand, but not while typing. But the ones I know who have been typing since they were extremely young, or have just been typing for a long time, often say they can think perfectly while typing. I have actually noticed the transition in myself-5 years ago it was very hard to think deeply while typing, today it's completely natural.

An e-book searching system doesn't need to be nearly as complex as typing. For example, you could theoretically have a little scrollbar that you drag your finger across and can easily anywhere from the beginning to the end of the book. In just a couple weeks I imagine this would be totally natural behavior.