Judging by this - http://doctormo.org/2011/04/12/how-to-make-a-gnome-login-screen-in-python/comment-page-1/#comment-11483

I suggest it is a case of 'rewrite what you don't understand' - the rest is rationalizing on the part of the author. Its a shame that trivial developer whims impact the direction of a major distro so much.