I think the video speaks pretty well for itself although I can understand some questions people might have.
I've been training in Systema for a little over two years and have trained with Vladimir and Mikhail so I had some reference. I was at the seminar the film was taken at. Besides Systema I trained in the Bujinkan for 16 years. I am a police officer and have attended defensive tactics, baton and firearms instructor's schools.
Anyways where to start? First I would like to say Vladimir and Mikhail (guy in the video) are very very good martial artists. Mikhail and Vladimir are both former Spetsnaz guys. I haven't seen their Spetsnaz membership cards

but have seen enough to believe them.
Second the training IS sometimes cooperative in nature. Early on it is important to help your training partners relax so they can move efficiently and creatively. If you apply too much pressure too soon people have a tendency to seize up, hold their breath and stand flat footed. This could be deadly especially when dealing with larger, better skilled or armed adversaries.
Often people roll or take interesting falls because they DECIDE to. This does not mean they did not lose their balance though. This is so they don't fall on their knees, elbows, back or head. Seems like a sensible alternative especially on a hard floor. To resist falling often means teeter tottering on one foot in front of your partner who could very easily strike you or cause you to crash in a less gracious manner.
Third people often mistake training videos for what a martial art would look like in real combat. Kind of silly since training partners don't want to risk having their heads knocked off or shoulders broken just to make a convincing video. It is much better to work at a relatively slow pace and follow where the force is taking you. Otherwise bad things can happen including unforseable accidents.
In real life people aren't going to flip in the air and do somersaults (generally). They are going to YELP! and hit the floor in a heap. Not nearly as cool looking though.
I remember being at a Vladimir seminar where he was showing some really impressive and dynamic work. After Vladimir was through and everyone walked off he commented that much simpler work was all that was necessary but that people liked seeing the complicated stuff. I was really taken aback by his honesty.
When you watch Mikhail he usually is very straight to the point. He usually ends things with a couple well-placed and well-timed punches. I spoke to one of Mikhail's 20-year students while in Moscow and he told me many stories about Mikhail knocking out opponents on the street (including himself twice when he challenged him early on).
Mikhail and Vladimir are certainly the real deal however beware of making too many generalizations from videos.
Jeff Sherwin