Tolkien had a very unique medical condition; absolutely massive appendix

It's my experience that they're depicted as somewhat awkward hyperlinks in the book to the (howeverthefuck thevpublisher formatted them) footnotes and back.

Depends on the reader I suppose. But in my expirances, its much much worse. You see, in a book you can quickly flip back and forth between pages. Moving bookmarks takes no effort. On a ereader you have to pick your page via a menu, go go your book marks via different menu. Delete bookmark via menu

Menu menu menu click click click its awful.

Got a book with a map at the front? Well you better memorize it because its not worth the effort to flip back and forth when ever some location comes up.

That's nothing compared to reading Ulysess, already a giant tome, and carrying the even bigger annotations as a separate book around with it, that you need to look at roughly every other sentence.

Gotta mention House of Leaves, too. Another double bookmark book.