Sorry if I offended you Belichick disciples.
When the ball is at the 5 yard line there is not an official near the coaches. All of the officials are at the goalline. What do you want the guy to do? I've done this a number of times when coaching at lower levels where there might be only 3 or 5 officials.
Yes, what he did was legal and allowed. But he certainly made show of it. Like you, I've been involved in football for years on the middle school, high school and college levels. And rarely have I seen coach run that far down the field. I guess my point was lost, which is the fact that his actions scream "look at me."