RoH? when I am add tanking, I use the Riot blade chain to get me as much MP as possible and use flash of light + Circle of Scorn for AoE aggro. When they go down to 2 targets, that's when I switch to RoH chain, I usually pop Fight or flight + Bloodbath (great for aggro generation thx to self heal), I almost never do Flash of light on 2 or less targets if I have those CDs ready. Riot blade chain is also faster burst damage, RoH might result in higher overall damage.

To me RoH seems like great on paper but I have always done a much better job spamming flash of light with riot blade to back me up on MP generation. Even when I have hasty DPS in my group that will start DoTing or AoEing right off the bat, or even with healers who cast regen on me, when I switch to the flash of light spamming routine, I can get the aggro back and keep it.