Originally Posted by Jellby
One: For consistency, it also let's you know if the TOC is at the end of the book or not, and whether there is anything interesting before/after it.
Two: In this case they are different TOCs. It's a link in the off-line TOC to the in-line TOC. The in-line TOC can have additional information, like illustrations or short summaries, which are not in the off-line TOC, and there should be a way to reach the in-line TOC (if it exists) that does not involve paging forward/backward all the way.
OK, I can see #2, but I guess I always strive to make sure that the offline toc is exactly the same as the inline toc (if it exists). *shrugs*
But like I said, I agree the decision should be made by the creator and NOT iBooks implementation of the navigational toc.