I don't believe it was a matter of poor training. You can get all the training in the world and it'll do you not one whit of good if you don't apply it. It was more a matter of poor mind-set. It seemed the LEO's attitude was "Business as usual, just another routine stop." And things went seriously sideways from there. The LEO was fortunate that the assailant seemed more interested in beating the snot out of him than trying to take his pistol.
"But officer, Alcohol, Tobacco and Firearms are three of my favorite things."