Couldn't disagree more. Take a class from law enforcement trainers (for a law enforcement perspective) and you will discover that much of what he is saying is correct ABOUT LAW ENFORCEMENT TRAINING. This is the perspective from which he is generally speaking.
As we have seen from his example, if true, that not all martial artist would stay away. And I have also seen, either personally or through reports written by police officers, where those who have had some type of training do get involved in situations they should otherwise stay out of. And most of those people are cops, who should know better than to get into off-duty incidents.
Agreed, most of what I have seen is that people who handle a knife in this manner are those that do know how to fight with one.
Agreed again.
I think you are misunderstanding what he is saying here. I don't believe he is saying that this is how sparring should be practiced, but how it is often practised by martial arts schools with which he is familiar.
More importantly, I think that what he is saying is that a lot of striking methods that are taught are inadequate. And having taken those classes, I would completely agree.
And you help prove his point. Most fights don't start from a "guard" position. They usually start when the defender (officer) is not in some type of "guard" position. Training to fight beginning in only the "guard" position doesn't allow for the spontaneousness of the street. And the direction from which one is attacked is not always directly to the front, rear, or side, but usually somewhere in between. That is what he is refering to as that angle of attack.
I would suggest that if you took a serious look at what law enforcement officers have to do, plus the training (or more likely, lack of training) that they recieve, you would find that his arguments have extreme merit. And it is from this perspective that he is speaking.