I get your point but I still disagree. I agree that the situation escalated to the point that it did in part because of the officer's handling of the situation. Should the officer be as courteous as possible? Absolutely. Does an officer need to have "thicker skin" than the average person? Sure. But the driver was clearly out of line well. Now, because this officer didn't handle the situation as he probably should have, should that prevent him from reacting to a potentially threatening situation as any other officer would when a suspect returns to their car against instruction? I think not. I'll grant that the driver was only pulled over for speeding and that he didn't have any outstanding warrants, but that does not foreclose the possibility that he could still want to hurt the officer. At the point when the officer pulled out the taser and tried to place him under arrest the driver should have complied, but he didn't. You see the situation as mainly a contempt of cop / "ego" situation. While I see that issue in the video, of greater importance/weight to me is the possibility that the driver could be returning to his car for a weapon.
Again, if the guy were inclined to shoot the officer, he already had ample opportunity, and if he had a weapon and had thoughts of using it, he would have had it on him. The guy was just an unhappy speeder with a stubborn streak not a individual presenting a threat that justified tazering him.
Had the officer backed off handed him the unsigned, ticket and said "have a nice day sir and please drive carefully" the incident would have been over with the guy never leaving the car.
Alternatively, had the officer said "I am sorry sir, but if you do not sign the ticket I'll have to arrest you (forgetting for the moment the 'refused to sign' option), how would you like me to handle this?" the situation would have been over as the suspect was most likely rational enough to figure out that signing the ticket was his best course of action.
Instead the officer fils to give the suspect enough information to make an informed choice and compunds this mistkae by abusing his discertionary powers to launch the traffic stop equivalent of a thermonuclear premptive strike. I suppose by your reasoning, the susepct is lucky the officer did not shoot him.
In the distant past when I first became involved in criminal law and law enforcement the research was already clear that departments that adopted shoot to kill policies killed far fewer suspects than departments with shoot to wound policies as it removed the illusion that less lethal force was an option in situations where killing the suspect would not be justified. Sadly, the tazer in many respects represents a return to the less lethal/shoot to wound mentality. Had the officer had only a service pistol, he most likely would have not seen the need to bring it out of the hoslter as the consequences are more dire.
I had an aquaintance and dive buddy once who was an LEO in a medium sized and fairly safe city. In the space of 2 or 3 years he was involved in 3 of the 4 shootings made by police officers. All the shoots were justified under dept policy and state law, but at some point when you look at the situations and attitudes of those involved, you have to conclude that there is a big difference between a shoot being "justified" under dept policy and a shoot being preventable. I'd prefer whenever possible to have an officer that can de-escalate a potentially violent situation rather than create a situation where the use of force is justified or even required and I am sure most taxpayers and citizens would agree.