How does the He-800A's presser foot lifter work and what are its benefits?

The presser foot lifter is driven by a pulse motor, allowing the height to be adjusted as desired for when the pedal is at neutral position and when it is depressed forward or backward in two stages. The presser foot rises only by the height necessary, which shortens the time needed for it to rise and drop, making insertion and removal of material easier and reducing working fatigue. (Page 1)