Thanks for the thought! However there were a few reasons I ruled out a potentiometer. The first would be repeatability of run times. All I want is 2 modes, low and high with predictable battery life. Second, audio taper pots, which is what I need as the way we interpret magnitudes of light and the loudness of sound are both logarithmic functions, may not always be available in a replacement size. Mechanical switches will be around in their current form for a very long time.