Help with Diplomacy skill
 

I should be able to hire similar units from the enemy based on the skill discription but I cant get it to work.
I hire 1 griffon, go attack an enemy composed of only griffons after combat, I still only have 1 griffon.

Do you have leadership for more griffons? It only works if you have room. And does enemy have more than 20 griffons. It takes 5% so only works with 20 or more.

I don't really think it is good way to build army. It is handy for occasional replacements but not worth investing more than 1 point I think.

Yes there is room because I only have 1 griffon just 1, the enemy has 56 griffons. And just to make sure, I kicked out my dwarf canoneers and alchemists because they are different race. Still no luck.

don't bother with this skill, 5% just sucks, there's a lot other, faster ways to recover lost units

I already put some in a while ago, I thought I might as well use it instead of really wasting it....

don't bother with wasted skill too:) I wasted runes for 3 skills I don't even used few times and I've hit more than half game with a little sucky character. Little trouble is more fun:P

Could someone please help with getting the skill to work?

well, if you are going for priest upgrade skill, 1 point in diplomacy is required