Meaning: Also called "double clutch downshifting," it's a technique that allows you to downshift more smoothly while saving wear and tear on the syncros in your gearbox (assuming you're driving with a manual transmission; if you're driving auto, this doesn't apply to you). Old-school manual gearboxes didn't have syncros, so this was a technique borne of necessity -- without it, you'd grind gears while downshifting. In modern times, well-executed double clutching simply makes your driving smoother. While you really have to feel it in your car to make the most of this info, the basic steps in order are: clutch in, pop it into neutral, clutch out, blip the throttle, clutch in, downshift, clutch out. We can't stress this enough: don't overthink it. It becomes smoother the more frequently you do it, and you'll know when you've mastered it because it will a) be second nature, and b) you won't feel a thing because it will be so smooth.