I thought dielectric silicone was to keep moisture out,
That's a biggie. Yes, yes, yes. to prevent corrosion of the two metals that are making contact. Essentially no oxidization so you always have a good connection.
It is also an insulator, so I really don't think one should be applying it to the contacts. I don't think it has much to do with releasing from the porcelain but I could be wrong!
Ever dealt with anything American? Try getting original wires off of a 2.8/3.1/3.4/3.5/3.8, the rear bank.
It's easier to snap the end of the plug off with a prybar, than it is to attempt to get just the boot off.
Yes, it is used as a release agent.
Actually, I just found this, it seems to support what I wrote: http://en.wikipedia.org/wiki/Silicon...lectric_grease