There's been a lot of posts lately about dividing provincial borders.
As I see it, the provincial boundaries aren't present just because
somebody drew lines on a map. This is Birthright! Divine rule of kings
by bloodlines! To me it seems that provinces tie into bloodlines in
some way. Look at the map. Most provinces are the same size.
Coincidence? No. (Re: play balance). There's also an obscure
reference to province sizes somewhere that states that they cannot be
divided, but I can't think of where. But even from a game mechanics
standpoint, it's not right. Allowing players to create provinces at
whim from existing provinces is a bad idea, allowing for all kinds of
abuse; it also creates a whole slew of new problems: movement of
armies, ley lines, realm spells, etc... I've really thought this over
way before these posts came out, and the only thing I can say is that it
wouldn't work.