"** There is simply no silver oxide formed at room temp. "

Unless you got some qualifiers for that statement, it is not true. If true, what is that **** on my silver candy bowl ?

"Even the smallest leakage current can be a disaster with electronics - track to track on PBCs or between plate and grid pins of a vacuum tube or its socket. "

I would still not use anything that is not residue free on a tube socket. Either that or clean it off with solvent(s) that are residue free and make sure the residue is gone. Actually, it seems to usually be the tube pins causing the problem more than the socket.

"Products like WD40 are certain to cause no leakage. "

Unless it is sealed it is still a good idea to wash it down. There can be conductive stuff in the dust in the air and it can stick to the oil residue. So maybe the oil is not conductive but the resulting goop is. It really does depend on what you're cleaning.

And cleaning high voltage pots is clearly contraindicated. Like the focus and screen controls on a TV, or similar ones going to the CRT in a CRO. However they very rarely need it.

And what most people do not realize is that in a pot, usually you are not cleaning the carbon element, you are cleaning the contact for the wiper.

Talking about stuff becoming conductive, in my bigscreen TV days there used to be coolant leaks. It would leak but it was not conductive - YET. After electrical potential is applied for a time the **** became not only conductive but corrosive. Many nightmares over that. Soaks into the board and screws that all up, eats the copper and the pins off of components. And nobody knows until the failure happens. And if it leaks onto SMPS, HV or line output section it can cause a fire, so manufacturers started installing gutters..

And let's not go too much into when lytics leak all over the board. I have had to run some through many cycles to get them clean.

And it doesn't take high voltage to make a problem. Last year I worked on a fairly expensive Roland drum machine. the output OP AMP was misbiased at the input and I could not figure out why. Well later I find the board with the output level control had been doused by some sort of contact cleaner, there was residue all over it. I cleaned that ****er many many times and it didn't work. I had to modify the thing to tolerate the leakage ! Actually a 47K resistor to ground did the trick.

Whenever I go to a shop and they give me a can of cleaner I spray it on a paper towel. I want to see it COMPLETELY dry. Pure TF, though not the best cleaner, you could be sure there is nothing left of it and fast. But that is pretty much a form of Freon and you can't get it in the US anymore, except maybe in the military or under some special license. I got some Freon 12, maybe ten pounds of it and if I sell it that's like $100 a pound and I want to first see the car it goes into hold a nitrogen charge for a week at least.