Ongoing Damage is not a Controller feature

[Tony Vargas]

Ongoing damage isn't inapropriate for controllers, but tacking it onto a power doesn't make it a 'controller power.' It's important to recall that the controller role is not exclusively about inflicting conditions or restricting enemy options. The PH definition of the controller is broader than that. Monster controllers are more focused on inflicting conditions, including ongoing damage. They're different from PC controllers. Monsters, for instance, don't often need to sweep minions away with AE attacks.

Ongoing damage could be seen as exercising some 'control.' It puts an enemy under pressure - it's taking damage every round, and that might alter it's behavoir. In a strict mechanical or metagame sense, it probably won't alter it much (if anything, it might encourage a monster to go more heavily offensive, since it has 'less time to win the battle'), but if the DM runs monsters in a more considered way, they might react to it with rage, fear, or whatever.

 

[Belphanior]

Ongoing damage, by itself, doesn't make a power very "controller" flavored. I think it's inherently more of a neutral element that can fit with all roles. And it's not as if classes need to rigidly stick to their role at all times. There's also leader and striker powers that mark, for example.

As an aside, Fire Shroud does strike me as a decent controller power. Controllers (both monster and PC versions) often have powers that evade or discourage melee attacks, because they're typically the most vulnerable. A close burst 3 attack that discriminates between allies and enemies? Solid gold for a controller. And it would probably be way too good to give it to the ranger, because he won't have to refrain from getting into the melee to use it.