and you use a level 81+ to attach it in a perfectly legitimate way to your weapon and then send it to any other character just like you would any other BoA item. Everything you do to obtain it is completely within Blizzard's intended game mechanics. If they really did not intend it to be used in this way, you would see an item level requirement like so many other enchants have.
I'm sure many people have been reporting this "exploit" and somehow I have yet to see anyone have action taken against them while people that were using gems were catching permabans within the first couple weeks.
We'll see how things play out and if Blizzard steps in.