That's even more important on an older unit when bleeding the brakes period, trash & possible corrosion builds up past the normal range of travel, guys get in & start burying the pedal in the carpet wrecking the seals & getting trash all over. Let it gravity bleed & easy does it when it's time to pump. Not to mention pounding the pedal can pop the pressure differential over & old ones sometimes won't move back, making it impossible to bleed or get a good pedal.
