Yeah the wiki says Ice Cages are roots and I'll be checking mine now but I believe it, just was a surprise.
The wiki *does* say for Presence, on the Presence page, under effects: ◾Increases the duration and health of all Crowd control effects - they just used the term 'holds' for some reason on the general description at the top of the same page.
Snare doesn't seem to be overly useful in CO but that's interesting to find it on the Crowd Control page. I would have considered it a debuff. I'm kinda surprised Placate is considered Crowd Control in the wiki list too. Self crowd control maybe..
In my mind, Paralyze and Sleep are both holds - when a mob is paralyzed or slept he is held and can't do anything. In CO, he can try to break free, which is one step up from being able to do nothing.
Roots I consider Immobilize. Which is like a Hold but the mob can still attack.
Stuns are in their own class and considered.. stuns. One thing about stuns is they are generally short duration and generally all or nothing but in CO they can have their duration reduced with a high CC resistance, apparently.
We all know Confuse.
All of these things control crowds differently but they are all still the same thing - Crowd Control.
I still say snare is closer to a debuff and placate seems so too. Crowd control, to me, is a group, not self only, thing, and it generally involves some kind of lockdown not just a (speed debuff) hinderance. But I guess there is no debuff resisting, sooo, there we go, voila, they are crowd control, a thing we can have resists for.
Overdrive is supposed to fire off whenever a maintain is held for half duration or more and Conflagration from the Fire power set is definitely a Maintain but it won't work with Overdrive. Maybe you are seeing a similar situation with "Wither" not triggering on BoA.
*shrug*