[Toomuch]

Don't get trolled, mobs are social.

It's a slightly different social than classic though, because people learned how to abuse the old system and bards could solo raid mobs (not working as intended, despite being super freaking cool). It had to do with charm, and faction assist. If I'm not mistaken, the code change was for that reason, so swarm kiting is out, because the extra mobs just chase YOU now instead of gang banging your pet.