First one which I dont like - kill the right one first, the left one then Commander. I dont know what ppl find good about this tactic. Basically two first targets are untauntable and are chasing targets pointed by commander so You have to kite them if tehy're after You until they die.
If you're attempting to kite a boss just because you have aggro, you're doing it wrong. You're just making it harder to heal you and reducing the damage the rest of the group can deal to the target you're taking on a merry romp through the battlefield. The entire reason that this kill order is used, which has been described several times over, is because of Heavy Pin. By killing the big guy first, you reduce the amount of time that someone stays channel-stunned. This gives you more total uptime, albeit at the cost of the sword boss getting to beat on whoever he so chooses. It's not as if any of the bosses except for the main boss really deals that much damage. The sword boss is killed before the main boss because he's got less hp than the main guy and one of them has to die to make the remainder follow a normal aggro table.
The basic difference between the two strats is predicated upon a difference in how the various mechanics are valued: the right-left-middle strat considers the stun to be the more dangerous mechanic; the middle-right-left strat considers the lack of an aggro table on the other 2 bosses to be the more dangerous mechanic. Neither is more "correct" than the other, since, as has been evidenced time and time again, both strats have been demonstrated to be effective in roughly equal measure. The more important factor is that the group agree upon a specific kill order rather than having DPS split, prolonging both mechanics to the general dismay of the group.