While I wasn't particularly enraged or irritated with it or anything, I did find it a strange thing.
Still in the process of leveling my first tank, and running Aery. There's this WHM and SAM in the group that I'm pretty sure was one guy dual boxing. These two characters acted strange from the very beginning. So I make the first pull, the MNK and I are the only ones really attacking while the WHM is keeping me alive, and the SAM was just afk over at the start of the dungeon. Never said anything, just wasn't moving. Then when one of the two mobs died and the damage I was taking lessened, the SAM started moving. He hit Diversion for some reason and came towards me. While the SAM is moving the WHM isn't really doing anything, SAM gets there just in time to help finish off the last few bits of HP on it. No big deal, move onto the next pack of three as a whole group. SAM just stands there while the WHM is healing me and the MNK and I are doing all the killing. SAM starts helping again when there's one mob left. This next part is the funny part. We get to the first boss and engage it, the WHM hits me with a Regen and Medica 2, then just stands in melee range and auto attacks, then the SAM kicks it up. The fight goes smoothly until about, say, 35% HP left on the boss or so. The dual boxer is so focused on dps'ing as his SAM, he doesn't notice his WHM get hit by the tether. When he finally does notice, the WHM doesn't even sprint, just runs straight forward towards the statue directly across the way from him and doesn't make it. WHM dies, and we somehow make it through the rest of the boss without dying. The rest of the run I didn't notice anything out of the ordinary and the run went fine after the first boss, but I still think it was a dual boxer. I suppose it could've been 2 people in the same room, but one had to afk as the queue popped and the remaining 1 tried to play both to not get either of the characters kicked, but it was a REALLY strange start, y'know?