While I do think that current implementations of digital books are very lacking and thus don't compare as well with physical books as they could, this is one area I have to disagree.
Flipping back through a physical book requires a process of trial and error while looking for that previous page, or referencing the index. A digital book usually comes with a search function that can knock that out a lot quicker.
> Flipping back through a physical book requires a process of trial and error
And yet I am so much faster at finding that vaguely remembered section or passage by using that process of trial and error in a paper book than I am on an ereader. That physical third dimension makes it so much easier to remember roughly where it is.
Flipping back through a physical book requires a process of trial and error while looking for that previous page, or referencing the index. A digital book usually comes with a search function that can knock that out a lot quicker.