If the idle speed is set correctly, there will be little or no ported vacuum on the line, at the RPM he needs to prevent the centrifugal advance from kicking in- - - -usually 500-600 max.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!