[ProDigit]

I am, just as I could call you 'imbecilic' too, like you so generously spread around; but I'll refrain myself from using those words!!

But I'm just saying that it makes no sense to make things complicated when ithey could have invented a very good and optimized code formatting, especially if it's for mobile devices where every code line just consumes unnecessary CPU!

And aside from that; I'm still interested in what lines one can safely remove without breaking the epub, meaning I don't really care of not having an epub with all bells and whistles, since I am mainly going to use the epubs in hardware Ebook readers instead of on a pc which supports external links and all other advanced stuff like library organizations etc...

on my ebook reader I open books from file structure, not by author.

And I'll repeat:
What is the use of including external http links when the device can't connect to the internet anyway? Unless these lines are purely informative, there's no reason to keep them in the book, and certainly should not be made a requirement for ebooks.