Extra defensive stats of 1h are not "amazing", they are not worth having over two times less damage with skills. As I said, I could see 2h/dw doing maybe 30% more damage per AP over 1h with skills/auto for a fair tradeoff with survivability.
Hail Strike is OP for 1 AP too, but it's a different topic.
It also depends on the quality of the offhand shield. Were my 1H warrior with a shield worth 72 armor points, +2 str, + 10% fire resistance and +0,5 meters of movement to face, let's say, alexander in a 1-on-1 fight, my 1H warrior would win thanks to overpower (more physical armor), rage, battle stomp and bull rush to keep his opponent permanently stunlocked, and this is despite alexander's monstrous damage. Frankly, I don't really believe that imposing 1 extra AP point cost to 2H warriors skills would be a fair way of balancing things.
Nerfing the damage output of cripple, bull rush, and rage, on the other hand....
