Power Bleeder for clutch fluid flush

[It'sNotTurboTime]

Last night I flushed my brake/clutch fluid for the first time (it was mostly not a disaster). The general consensus seemed to be that the clutch is stubborn and you need a power bleeder to get any air bubbles out so I bought one.

Brakes were fine, pressurize the system, open valve, let the old fluid out. I assumed it was the same for the clutch. However, I opened the valve, nothing came out. I pressed the pedal to the floor, a little drained out. I thought it would keep draining but it didn't.

I ended up opening valve, press pedal to floor, close valve, pump pedal by hand till firm, open valve... etc. Very tedious climbing under the car and back out over and over.

This leads me to 2 questions:

1. I must be doing something wrong. Anyone else have a way that worked better?

2. I'm also not entirely sure if I was accidentally introducing some air to the system. When I pressed the clutch pedal to the floor, there was a very small amount of spring back at the very bottom of the pedal travel. If you were doing this two person method, you'd close the valve before the person let off of the pedal.