I remember an advice I read somewhere: during bleeding procedure do not push the pedal to the floor, because the travel of the M/C piston is limited in normal use of the brakes; that is, it normally does not reach full stroke, so creating a tiny step or the like on the M/C inside wall. This difference on the surface may scratch the piston seal if it reaches farther. To avoid this, it was recommended to place a block of wood or other suitable material under the pedal to limit its travel to its normal amount only.
Is this real?
Fabio.