[Usability] GtkNotebook scrolling

[Cody Russell <bratsche gnome org>]

I brought this up on desktop-devel-list and gtk-devel-list hoping to get
some usability feedback, but the responses have been more of the "hey, I
use that sometimes!" type of response which isn't what I want.  But then
Cosimo mentioned that we have a real usability list, and so here I am!

So, I stumbled upon this feature we have where you can use mouse-wheel
scrolling on GtkNotebook pages to change to a different page.  It wasn't
the most pleasant experience for me since I did it on accident and was
briefly quite confused.  I'm not a usability expert by any stretch of
the imagination, but my gut feeling is that if something confuses me for
even a moment then it might be a usability flaw for average users.

I mentioned the issue to Matthias Clasen on irc and he seemed to agree
with me.  But I want to get some feedback from people: are there really
good use cases for this?  Is it something that should be explicitly
enabled or disabled in certain places?  Does it make more sense if you
have tons of small notebook tabs?  Is it something that could be
configured somewhere?  Or maybe I should just leave it as-is, or maybe
rip it out entirely?

/ Cody