Yeah, I do it for fun sometimes. I test them to see which enemy will win the fight :) And i have seen some epic fights :)
One time I found 2 star fuling berserker at the border of plains and black forest (but didnt go too close to agro him)... i decided to find a troll in BF and make him chase me back to plains. I was extremely lucky and within a minute i found 2 star troll and a greydwarf party. I expected this will be another epic fight, but i didn't know there were actually two berserkers and another fuling with a spear so it was actually pretty quick death for a troll :(