I don't think anything should be considered overkill on a card like this. The whole damn card is overkill
(at least for me it is)
I think it's good that there is 4gb per gpu. Just as someone else pointed out, this overkill card will be powering/running an overkill monitor setup with some sort of massive resolution. Which is when the 4gb per gpu will come in handy, plus bragging rights for owners of this monster.