I seem to recall that there was a Silicon Valley startup that did this a couple of decades ago, probably with the two circuit version. A neighbor of mine at th

I seem to recall that there was a Silicon Valley startup that did this a couple of decades ago, probably with the two circuit version. A neighbor of mine at the time was one of the principals. IIRC they failed to get traction because of manufacturing costs in spite of the improved efficiency. But it was quite a while ago and the details have faded into the mist.