1/4 panel skins

Has anybody used a 1/4 panel skin as A 1/4 PANEL SKIN and not a 1/4 panel replacement? A body man I was talking to at a recent car show said the 1/4`s available for our cars are meant to be used over the existing panels not in place of them, that`s why they`re lighter gauge. Has anybody actually installed a 1/4 this way?