Well I can see a few benefits if it's implemented unrestricted, mostly it will add more depth to torpedo gameplay. As long as the change reaches it's goal, creating torpedoes which actually WORK against certain targets, and it adds another level of skill requirement to DD's I am all for it.   Why would I argue for battleships to be forced to select HE to shoot at destroyers, and then not fully support the addition of a choice for destroyers to have to make a proper ammo selection?   The only reason I would not do that is if I knew 100% sure WG couldn't actually pull it off in a balanced way. And I think they can, as long as they have enough reason to do so ( big company, lots of resources as long as you can motivate the right people I guess  ).