The end of all traphic jams

A simple proposal: every motorist on public roads has a radio on board his vehicle. On a nationwide frequency, a tape plays this message "one....two...three....now!" on a ten second loop, just like the old machine one could call (does it still exist?) to learn the exact time.

Once people get stuck in slow traffic, they tune their radios to that frequency, and as soon as the tape reaches the "now!" part, everyone kicks down their accelerator simultaneously. Bam. Everybody driving again. Problem solved.