I avoid this from happening by using two feet. Keep the left foot on the brake, and with the right foot, give it just a little gas, then when you let off the brake, it won't roll. I also use this in traffic, at a stoplight, when the vehicles in front of me don't get moving very fast. If I just move from the brake to the gas with one foot, it will take too much pedal to keep from rolling back, or keep from not moving at all, which is not what I'm used to, all other automatics I've had creeped forward without pushing on the gas, but with the Enclave I have to push the gas, or it will just sit, in most cases. Also, I think it's a good idea to either apply the parking brake on small to medium grades, or slowly release the brake after putting in park, don't let it just roll and catch hard in park, not sure if this could damage something. Keep trying different things till you are comfortable to how the vehicle reacts, it's nothing wrong with it, just different.s