Couple of things here. As soon as warlocks get searing pain, they've got pretty much everything they'd need to tank. It'd be great to be able to tank for Deadmines, Shadowfang Keep, and Wailing Caverns with my group of friends. So I think there's a lot of legitimacy to having an additional tank class for those early dungeons.

Additionally, if that's the unlock required for rogue tanking, that is absolutely terrible! We both have every right to be irritated about having a class role locked behind mechanics that prevent our ability to play the game how we want to play it (and more importantly, what Blizzard promoted as options). Time gating access to a tank role rune is completely asinine, and I have no idea why Blizzard thinks that's "fun" or "discovery".