First, show me where H.D. admits it's a mistake! The gear noise is from 1st and 5th having straight cut gears, where as 2nd, 3rd, 4th, and 6th gears are helical cut. Higher torque gears need straight cut for better performance and load. The "Isolated Drive System" is not a "fix" for gear noise. It's to help smooth varying loads to the drive train. It's also installed on the VRSCA (which there is no "complaint" of 5th gear noise). How long do people ride in 5th gear to find the gear whine to be that annoying? I find unnecessary rider whining to be annoying! Go ride a shovelhead!!!