Hello all,
Wow! Great discussion! One of the longest threads I've seen!
Were at a trade show, so sorry for slow response.
The original intention of the no duplication rule is as follows:
Players should not knowingly put a copy of an enchantment (same name) on the same target. For example, if you have a face-down Block on your creature, you cannot put more face-down hidden Blocks on him. If your creature has a revealed Bear Strength, you cannot put a second Bear Strength on him face-down asa "backup plan".
If you reveal an enchantment (pay its reveal costs and flip it over), and discover that there are any other revealed enchantments in play with the same name on that target, then you have to destroy the new one you just revealed.
Players cannot reveal enchantments on a target to destroy the new enchantment which was just revealed. So, you cannot use a face-down enchantment to counter a new one (as a "vaccine").
The first revealed enchantment take precedence. Any others revealed later are destroyed when they are revealed.
That should be fairly clear, and I believe the original intent is in line with what most fo you seem to feel makes good sense.
What is not clear is: If someone reveals an enchantment and you know you ave a face-down one wit the same name - do you have to reveal it right away and destroy it?
Or, are you allowed to keep it there face-down, hoping to use it later if the revealed enchantment goes away? Of course, it is assumed it was placed on the target legally (before the other one was revealed and without knowledge of the duplication).
We can rule either way on this, and would appreciate feedback to add to the FAQ. I feel like the face-down duplications should be revealed and destroyed because they are "illegal". And without mana refund (simpler). However, lets get some feedback on this.
The good news is that this should very rarely occur, so the ruling we make should have little impact on the game.
Thanks everyone for the great feedback and well presented ideas!