I think you guys are just mad, cloak breaks way to much anyway. mark never fails to work, cloak breaks 75% of the time wasting 4k magicka and a GCD and you get nothing in return:) Its one of the only skills in the game that has a chance at failing to work and punishes the person for it. As well as has numerous counter play options that arent just mark, but All AoE, some Dots still break it, their is even a whole potion dedicated to it for magicka players. Mage light and expert hunter both counter it, even more so with how good expert hunter is for stamina it should be on your bar anyway. Oh and by the way lightning staff heavy attacks still break it, so just do that if you're that lazy:)
Because cloak is not strong enough apparently, that's also why you can cloak nearly all damage in the game (including destro ult, dawnbreaker, meteor, leap, ...) if you do it right, even siege damage
Invis pot work the same way, if not better though. I never get tired of invis potting on an NB attacking me out of stealth and turning the tables. Glad that mark got nerfed and glad Cyrodiil doesn't sell basic detect pots + no NB runs them when they run into non-NBs