Nice vid, but what they don't tell you is about the tension release you'll feel every now and again.
As you are running around the unit stays engaged when there is power being sent to the wheels, this includes when in a turn. The vid showed it being 'open' when turning but that is during a gliding, non-powered turn. You can tell that it stays engaged during a powered turn 'cause you'll hear one (the outside of the turn) tire chirping as it goes. The chirping is the tire relieving tension from the extra turns it needs to accomplish.
Now back to my first point, the chirping tension release won't always release all the bound tension. Every now and again you'll hear and feel a clunk in the backend. This is the teeth releasing for a brief moment releasing that stored tension. Scared the crap outta me the first time it happened. When it happens, depending on the amount of tension, the backend can feel like it jumps to one side (usually to the right for me). Is no big deal, just gotta be prepared for it and explain to your passengers what is going on.
Overall is a really nice locker. Fully engaged when powered and takes care of itself. The clunk is a little quirk that is kinda cool after you get used to it