Well ... i dont. :P (Just for the record: I dont like xp split idea ... rest is fine)
Why? If you face 3 imps, your first battle, and you don't do XP split, everyone in your party, all 5 characters, would gain 600 XP and level up. Using XP split would divide the 600 XP between your custom party of 5 and grant only 120 XP to each. This is more appropriate so that most of the prologue you stay at level 1 instead of being at level 3 by the end of the prologue.
See, it's already built for a party of 5 or 6 if you use proper stats and XP split. Otherwise, it's broken.
