David's brows knitted together in question there. "That's linked magic, I wouldn't want to trip any magical fail-safe or alert your... lovely former colleagues... that I'm doing." He pointed at the arm with all of the fingers on both hands, wiggling them as he twisted them away from each other while deep in thought. "It's tied to your magic, right? So I can't do that..." He flicked his right hand as he brushed an idea away from himself, wiggling his fingers again in thought before snapping them in a eureka moment.