The reason people block their driver is because they don’t release their hands or unhinge the club soon enough. Because the driver is the lightest club in the bag, it is the easiest one to hold on to. Players tend to over rotate their body through the shot and their bodies and never stop to release the club. An obvious example of this is when little kids swing and miss and spin around in circles the club never released. You have to stop your body to let the club unhinge. If you are able to unhinge the club you can rotate your hands which will close the club face which help keep the ball from fading or slicing.