Why putting full pages into quicktab is not a good idea?

If you put pages into non-ajax quicktab then the user have to load all the pages at once, and many times he will not read the second tab. So it is a waste of resources.

If you put heavy pages into ajax quicktab then sooner or later you will run into issue #359241: ajax loaded content can be lost with slow internet connection, where your visitor can't see the content and the site looks broken.

use (tab like) menu or create simple (tab like) links. If you load large amount of data then a page reload will not take longer than loading through ajax.