SM Graveyard Pulls

Is there something weird with the aggro in this dungeon specifically. Have done this dungeon about 5 times now, same thing each time:

The first square room, there are two enemies on the left, 4 in the back, and a patrol.

I wait for the patrol to head to the right/towards the boss.

I throw a knife at either of the two on the left, LOS in the hallway.

I get those two + the four in the back running into the hallway.

I watch youtube videos of this pull, people are not even LOSing and just fighting these two mobs in the room and the four in the back are not aggro at all.

I am multiboxing lvls 33-35 currently.

Not a big deal, but it becomes a clusterf and is annoying. Heading to library soon and hope this is not a thing.