Axle's page

I've seen an enemy call in a specific demon with a CR 5 higher than itself but the same or less amount of hit dice knowing that because of who's in the party the demon would ignore it and attack the party either way. The demon was called "Galundari, the Scourge of Heaven". Now despite the fact that the demon was 5 CR higher than the caller the party only got XP for the creature that called it and each creature on it's own is a party killer. Now this DM strictly abides to the rules as they are in the book but while I can find the rule about summoned creatures I can't find the one about creatures called or brought in by gate. Can anyone tell me where it is or is this just a loophole that the developers overlooked? Does it also mean a PC can attempt the same thing and get full xp for the kills caused by a stronger creature when he/she calls it?

Now here's the funny thing in older editions it was explained (when you found it usually in expanded releases) that nothing asides from pure air could pass through a barrier made of force not even magic hence it did work as a protection versus touch attacks at least with shield and mage armor as they automatically protected you from all angles. However I haven't found a specific explanation of force in pathfinder yet. It's perhaps one of the few things they forgot or just thought it was obvious. As players and GMs my group has always said yes but I'd rather look for a way to contact Paizo directly about it than take what anyone has said here as your answer.