Okay, so I tried this in the game, and I'm not sure if it's a glitch or intended or what.
Playing against Ambuscade and put Wrest the Mind on Reactive Plating. Someone hits Ambuscade, setting off Reactive Plating. I redirect the damage to Ambuscade. That also sets off the Reactive Plating to attack itself, which I again redirect to Ambuscade. Then Visionary does 3 damage (reduced to 2) to the plating, and 3 damage to herself.
Shouldn't she have done two instances of damage each to the plating and herself, since she redirected its damage twice?