i have experienced it definately.. twice while offroading almost with disasterous results because once my spotter was only a few feet in front of me and once coming down a very steep grade...

usually only happens when im wearing my workboots...

do you have pedal covers? my problem got worse with the addition of covers, so i drilled out holes in the stock pedals so that i could move my brake pedal cover as far away from the gas as i could, has helped some