I can see potential abuse (or what seems like abuse to me) here. What's to stop a character who is planning to use one of these from putting as many dice in defence as he can, having nothing for attack, and then when he makes his attack, doing a Special Manouvre (or roll for an Advantage) with its full dice?
I can think of one way to balance it, but I think it's too fiddly: you can only use your Name and/or Ability trait if your Name and/or Weapon die respectively are placed on your attack side, and the defender likewise only gets to roll those which are applied.
What are your thoughts on this issue?
Plus: it might not be an issue at all, since you aren't inflicting any wounds. You're just storing a bonus for later. But still...

I think you answered your own question at the end there. :)

Though there was an ellipsis, signifying doubt... :)

But if you consider it okay, that makes it fine by me.
Doing this kind of thing could also be an attractive option if the Positioning phase hasn't been kind to you.

Some people had ideas for alternate rules for Special Manoevres. I think it would be great if they posted them in this thread.