Unless you adjust up the parking/E brake,it's a waste of time.
Unscrew the E brake lock nut on the rotor/caliper end,then turn in the course threaded bolt till it bottoms,then back out half an ant's leg,and nip up the lock nut.
NOW the piston is where it should be-MAX- to not waste up any bleeding/adjustments/travels.
It makes all the difference.Same when you bleed the fronts... adjust the front shoes first.Then quicker better result.