Is Gladiator's Medallion really a must have for any serious kind of PvP? Even as a Human, Orc, Undead or Dwarf you would take it over other two Talent choices? Why?
I know Adaptation sucks vs Sap, but Relentless is not bad at all for some more tanky specs, who can survive a stun or two. What do you think? Which class, spec or race is less "Gladiator's Medallion dependent?"
I would say Human Paladin could play without it, Orc Warrior maybe and Holy Priest with that CC removal Talent every 30 seconds.
I generally only use adapt in BGs or in mongo arena comps when we don't face a rogue. There are generally instances in which you want to just sit a CC, but for those two instances I like it better. For BGs I like it better because you can stay mounted if you get hit with a poly while traveling. In the arena mongo comps it is just about getting that initial damage out as fast as possible and I use it there.
Of course, as you mentioned rogues present a problem with sap. I almost never use relentless though, I play a human and I switch between adapt and 2min as I see fit.
As a general rule I have relentless as a default choice for my healers. Especially my orc healers.
When playing DD specs I instead use medallion most of the time simply because being able to break cc's on you while bursting is hella strong. The only exception to this I can think of atm is on my orc shaman when playing ele - again simply because relentless + hardiness is really strong.
I could imagine any human running with adaption is also just fine since you have EMfH. Less so with undead since it feels like there is less fears in the game.
I think Blizzard has done a good job balancing those three talents as they fit different situations and I personally will be changing them all the time according to which comp I'm facing.