I suspect that the reason that gear vaults are restricted from the shared bank is to prevent someone from moving unshareable items from one wizard to another. However, what if the gear vault is empty? I don't mean empty of any "no trade" items, I mean completely empty. If it's empty, I should be able to put it in the shared bank so that another wizard can use it. I know it's possible to check if something's in it, because gear and pets are checked to see if they have jewels, so why not gear vaults being checked if they have items in them? If it has stuff, then it can't be moved to shared. If not, it can be.
I completely agree. Although I think that items should be moved along with the Gear Vault. It seems that KingsIsle has the ability to filter out No Trade items because it was done with the craftable mannequins and items inside houses. I don't see why this couldn't be implemented into the vaults as well.