I am thinking of trying to build a handheld throttle for my layout and looking for some advice. I am running DC. I have my current throttle/powerpak running to the track. I am wondering, if I could put a secondary throttle between the primary throttle and the track, ie: AC Wall -> DC Power Pack / Throttle -> Handheld Throttle -> Block Selector control panel -> Track On the handheld throttle there would be a DPDT switch to control the direction of the trains, and either a rheostat or a potentiometer to control the speed. My thought would be if I want to use the layout mounted throttle, I would crank the handheld up to 100% and use the throttle on the power pack, and if I wanted to use the hand held throttle, I would crank the power pack to 100% and control power flow with the hand held Any thoughts, concerns or suggestions to this madness?