He begins with a thought experiment that will come into play after he begins addressing Shermer's arguments.
You are late for a very important interview for a very well-paid job. If you miss it, you’ll certainly not get the job. You are driving to the interview and come to a fork in the road. As you are about to take the right turning, you witness a pedestrian being hit by a car in the other direction. The car flees the scene, and there are no other people or cars around. The hit pedestrian looks to have life-threatening injuries.
Notung points out Shermer's statement that we can "bring to [the question of morality] studies and data and experiments and research to see what works and what doesn’t." Notung rightly points out that "what works and what doesn't" isn't always clear and illustrates this point with the thought experiment.
Morality is about intention as much as result and Notung points out that whichever course of action one chooses, the result would "work" for whatever the person intended. If they leave the scene, their choice "works" to get them to the interview on time. If they stay and help, their choice "works" to give the man a better chance at survival. This was the same issue I had with Chatterton's piece about morality. Notung is describing very well the "is/ought" question in moral philosophy.
I don't have an answer, and I would like to take Chatterton and Shermer's viewpoint that we can rationalize a better morality, but there are holes that need to be filled before we can claim with certainty that this is true. However, Notung's piece is titled, "Science Has Nothing To Say About Morality," and I don't know if that is quite right either. Can the harm an action brings or reduces be quantitatively measured objectively? I've always leaned toward the same utilitarianism that Chatterton and Shermer describe, but now I'm not so sure.