I did not read the original article, but, if I am wildly optimistic, having a switch that has never seen DOT 3/4 might be a solution , easier than distilling something to get rid of impurities. I guess this shows there is a scientific background to our practical difficulties, but no real solution except to try it! I shall try, and frequently back up to a white object to make sure the lights work!. I shall also use LEDs
On to the next "problem"
thank you