Yes and no.
It's that perk we're talking about.
So let's say you're fighing a ranger and you almost killed him. You're ready to do last step of counterweight and he start to cast "concussive blast" or something like that. That's a stun. So, use your anti cc while the cast is running and you won't take the stun. You continue you combo without the interruption from the stun,and kill him while he run away screaming like a little girl with his bow on its hand. (while he puts a root trap and you already have root immunity anyway, to make the story sounds more realistic ^^).
About double tap, if you can manage to see a kb coming, for sure, the best thing to do is double tap, assuming you don't have kb immunity running, because in that case, you don't care.
And about the guy asking why people would go for armor, I'm feating this on almost every char for pvp. Don't understand how people play pvp without maximizing their survability.