The reason earth control wasn't very popular is because it fought itself. The immobilize and area immobilize attacks gave 10000% knock resist, yet it's possibly most useful ability was the thing that kept knocking people down. I can't be certain, but i think ice control had the same problem.
Ice Control did have that problem big-time, because it really didn't have much control if you took away Ice Slick's knockdown. Ice Control was still a very usable set IF (and pretty much only if) you paired it with a strong To-Hit debuff secondary like Rad, Dark, Time, or Nature. Then you could use the AoE Immob, put the To-Hit debuff on the mobs (or run into them if you used Time), throw Shiver in there, and the mobs rarely attacked, very rarely hit, for limited damage, and you had an AoE heal. Basically, you would allow them to attack but completely cripple their DPS. But without that, it was really weak since without a To Hit debuff, using the AoE Immob drew aggro, and -Recharge doesn't help when the mobs open up on you and kill you with their first 1-2 salvos.
Earth Control, however, did not have the same problem for a couple of reasons:
1: Its primary AoE control was an AoE stun, so losing the Knockdown didn't hurt it that much
2: Earthquake had a sizable (-10 enhanceable) To Hit debuff, so if you slotted it for -ToHit, you'd open up with a -15% To Hit debuff Knockdown patch. It also lowered Defense by 10% base, so you could open with EQ to limit the incoming fire, then hit with Stalagmites using EQ's -Defense debuff, and only then use Stone Cages. By the time that you negate EQ's Knockdown, the mobs are both debuffed and Stunned. And with the recharges on those powers, at higher levels the combo was usable pretty much every fight.
