Mushy brakes 4 life...

think about this bench bleed and how it works for a minute you have an empty bore in the mc so it is full of air so you hook it up pour in the fluid start pumping the pedal so when and if it the bore fills full of fluid means the air needs to go someplace and that is usually pushed back thru the system until it blows out one of the bleeders that can take a lot of bleeding . when you bench bleed the air is gone out of the bore and does not get pushed back into the system .