I've never seen it before till now. I've been to a Formula Drift competition before and never once seen it on the cars, of course that was back in 2008. Im sure things have changed since then. I believe the main cause of this is a type of brake oscilation which gives a more flexible means to allow the driver to apply braking power where he needs it. I mean its drifting not true racing. Where its the art of using the clutch kick/ ebrake technique. As a driver approaches his corner it probably helps adjust the braking on either side, which will allow for which wheels begins to spin the most as the car turns sideways. Just my theory.. thats all.
