The video shows:
1. The Air Buddy being disconnected from the power inflator control module.
2. Breathing from the Air Buddy
3. Re-connecting the Air Buddy to the power inflator control module.
The Air Buddy does not need to be disconnected from the hose. It can be used on or off of the control module. Taking it off allows you to breathe from it while holding the control module over your head to dump air on the way to the surface. No other BCD alternate air source offers that feature.