[Mr. Ivey]

The part you are refering to as a tensioner, is actually called a derailleur in bike terms. It's the part that picks up the slack in a bike chain. But we have passed that part. If you were to put a derailleur bot in front and in back of the power gear, and have them change orientation (the front and back derailleur move the chain up and out of the way from the gear that is being enguaged). One thing about a bike derailleur is that it has a bar under the gear, it's used to keep the chain from getting off of the derailleur. If you were to put this same bar, or a small cog to the under part of your tensioner, you would be able to lift the chain in order to allow the cogs to rotate and not bind. Just a though, it seemed easy enough to me to do this without possibably messing something up while shifting.
Ivey