Forbid this to ever happen, but if the parking brake was accidently engaged at 20 mph, what would happen........besides a WRECK!
Wondering, is there is a over ride when the transmission is in 3rd gear? If not, sure is a poor place for a switch...Ex: microphone for two way jumps out of it's clip and falls on the switch, engaging it. Don't care to find out the hard way, if you know what I mean!