MC bore area is a double-edged sword. As area goes down, pressure goes up for a given pedal force, and so other things being equal, a higher braking deceleration ought to be attainable. But if there are any compliances in the system such as caliper flexure, piston seals, flex cables, pad "wedgeness," or, of course, air in the brake fluid, then the pedal will feel spongier as MC bore area goes down, which subjectively creates the impression that the brakes aren't as "responsive" or as "firm." In other words, the pedal response is opposite to the braking response. The exact same effect is seen if the pedal leverage ratio increases: the braking force goes up, but so does the impression of sponginess in light of any system compliances.
Last edited by MAP; 02/02/12 11:44 PM.