Yeah, I've been riding a fixed gear for a while (lots of miles), with brakes. Skidding just came naturally one day, my brakes weren't adjusted right cause of taking the front wheel off all the time and one time I applied a lot of force to come to complete stop cause a car pulled out in front of me, and made a nice skid with barely any effort. Back paddling and skidding use, at least for me, totally different muscles than normal riding and I guess I developed them over time as I started to rely more and more on them to slow down and stop.