I don use CC at all on that HA, I tank them as they come. You have heard of something called the invested wurmslayer right? It works well because you are doing a lot of damage on these mass pulls with riposte, and you get the benefit of the permanent rune. Many of the mobs are half dead by the time it comes to kill them simply due to ripostes. I obviously have the usual over time buffs running like always. That does not change the fact that you can pull the entire wave on each step of the first HA and survive without too much effort. The biggest caution is avoiding AEs that you normally might use because there are often gnomework mobs in the area. And if you don't really want to mass tank, the mobs in quest start staggered out and walk to their destination, you can easily peel 4 or 5 off if you want to reduce the total number involved, and then each wave becomes even more trivial. If you want, you can also park your tank on the path leading to their destination and let them add over time if you are concerned about the delay for the mercs to get up to healing speed. Mass tanking mobs in the rest of TBL is far more difficult because (A) they hit way harder with much higher damage output, and (B) most have some sort of special ability that disrupts the fight through damage or some other means. A single mob in most of the rest of TBL can easily take you down if your healers are not on the ball. In GMM HAs on a single mob you barely even need a healer at all. There is simply no comparison between the difficulty levels involved.