From the tape I'd say that the cop was mentally totally unprepared for the incident. Had he approached the incident with the proper mind set his reaction time would have likely been much faster. It takes a moment for the mind to realize that this is really happening when going from a relaxed state. That?s the nature of being human.
There's a lesson here for all of us. Familiarity does breed contempt, and contempt is dangerous.
Complacency is one of the most common, difficult to overcome, and dangerous problems LEO's have today. At some point in their careers, almost all officers allow the word "routine" into their lives. Let's face it, if you made several thousand traffic stops with the only problem being griping about a ticket, you tend to loose that edge.
Even when we send officers to street survival schools, they come back for a few weeks ready to take on Rambo, and then slip back into complacency.
The human body... and mind, just isn't designed to remain in "condition red" for very long. It's very taxing, and the natural tendency is to step down to a more relaxed state.
It's a major problem for LE, military, and the average guy trying to cope with a bad neighborhood over a long period of time, and there are no easy answers.
Personally, I try to deal with it by staying at condition yellow rather than red. I try to stay relaxed but alert, aware but not paranoid, and I train hard so that my body and mind know when to go from yellow to red without really thinking about it or dwelling on it.
The first step though, is self awareness of the problem and being truthful with yourself. Once you've become aware of your own complacency, you've won half the battle.