I worked with several old timers in the 70's on all manner of relay control. One of them was a DMR ace, and he insisted that I, being the young helper should blow out those controllers, with a cadillac blower, annually.

The 1st time I did this of course the car would not run and I called him to the machine room to assist me. He told me.

"DAMNIT, Just KEEP BLOWING TILL IT RUNS. DON"T YOU KNOW ANYTHING?"...LOL...

It Don't mean a thing if it aint got that swing.

Cool, Free, Johnny Smith courtesy of NPR..HERE
http://www.npr.org/ramfiles/asc/asc25.smith.asx