The spikes and reactions were stress reactions measured by medical doctors from the monitoring of multiple signals (heart rate being one).

So they came to the experimental conclusion that (at least in this experiment) driving at the limit of what was possible in terms of speed the car could go and speed traffic would somehow allow was a factor of stress for the driver.

They also qualified the added amount of fuel necessary to drive the distance.

But they did not say one was better, one was worse. They just let the viewer decide on which variant they preferred.

And as I said: If the externalities were priced into taxes and cost of fuel - why not let people and the market decide if it was worth to them to arrive 20 minutes quicker on this distance.

Basically this guy made his scientific career by doing epic experiments where he observed communities of baboons during various social interactions, blow-gunned individual baboons with tranquilizers, then very quickly, took samples of their blood to analyze glucocorticoids (these are stress-response hormones and have a half-life measured in minutes).

Anyway, crudely stated, the major finding is that animals have intense episodic stress throughout their lives but never suffer health consequences from that stress because it's occasional. Humans, on the other hand, can get the same levels of "fight-or-flight" stress but at long-lived, daily intervals. Excessive glucocorticoids, over a long term, can interfere with the normal functioning of the body and precipitate a wide variety of health problems including heart-disease (and ulcers, as the title suggests).

In the case of driving, an aggressive lane-changing drive in a fast car might be exhilarating under certain conditions, but it's a different story for a daily commute. It's no accident that the advice given to people that experience aggressive drivers on the road is often along the lines of "Let him go, don't become a part of his bad day." Aggressive driving is a self-reinforcing bad habit that becomes part of people's identity in many cases. Personally, I don't care about the health of aggressive drivers, but I do care about their propensity to cause accidents and hurt innocent people.