I've seen a lot of multi-boxers but most of them don't use /follow and not to mention that you need multiple accounts to gain access to them and run some kind of program with them. i'll give some examples of them I've seen since cata.
1) on my human priest, I saw four hunters with a different race and a priest (I think it was a priest, so long ago with that match I don't remember). anyways I got farmed by them but the hunters were all scattered around mid. probably to prevent a cap.
2)another match happened with 3 pallies with different class specs. got summoned to the last couple of minutes. one was near gy, one was in mid, and the last one was escorting the efc. I think the same person was on my server with alli toons but were human pallies, but i'm not sure if the person is still playing or not.
3) one match with my tauren paladin, I was facing up against one human with four hpally draenei. the four draenei run around with this human and healed him or themselves. this multi-boxer was the only multi-boxer that I was able to beat, namly due to the bad gear on them or the other team mates weren't that good.
4) another match with my tauren paladin went up against three spriests, one in the flag room and the other two in mid. lost that one to them but I remember able to beat them near the last min.
5) this last one on my dwarf hunter had 3 24 multi-boxers. one was a hunter, druid, and a shammy. although we one that match, I really hated how that multi-boxer farmed me in mid.
compared to hackers/bots, multi-boxers aren't band worthy into submission because they’re technically the same person but with more people to control. also to be honest, I wish there were more of them out and about.
sorry for the wall of text, hope ya like reading the experience.