The original idea of a dual master cylinder is to improve safety. I know, duh. But wait, many brake failures are from other causes than a bad MC. A leak anywhere else in the system can put your pedal on the floor with no stopping power. Rotten brake lines and hoses, bad wheel cylinders and worn out shoes and drums probably cause more brake failures than do bad MC. I agree with Ralphy, it warrants a thorough investigation of the cause. A dual master alone may not fix it. Good luck.
