I think you are reading way too much hostility into this post. I think it's clear that David Samuels has a lot of respect for Coster-Mullen, all he's doing is establishing him as a "person," by giving his notable personality traits.
I thought this article was an inspiring account of how somebody with no formal training in the subject was able to recreate an incredibly complex machine, simply through his own intelligence and hard work. The sentence you quote is definitely not ridicule, but simply an accurate description of Coster-Mullen's approach, I certainly don't think the Samuels was intending to criticize a positivist worldview and most certainly not to be "corrosively anti-geek." Furthermore, through the article, Samuels repeats how impressed he is at how much Coster-Mullen figures out simply through basic reasoning, math and geometry, I mean it includes a complete description of how he painstakingly tracked down a vintage car so he could measure the size of a box in a photograph. I really have you no idea how you managed to read this article as suggesting that Samuels believes Coster-Mullen is deserving of ridicule, instead he seems very impressed, as does everyone else who is interviewed in the article. (Still not even sure how you got "anti-geek," Coster-Mullen doesn't even seem like a "geek," just a normal person with a family and a hobby, who is simply very good and dedicated at it.
An article that simply repeated the facts about what Coster-Mullen had discovered about the bomb would simply be his book. Everybody has their quirks, and an accurate representation of the person (because indeed, the article is about John Coster-Mullen, not the atomic bomb) should include more than a bare listing of facts about their life.
Of course it seems a bit ridiculous, but what hobby on such close inspection doesn't? I think reading it as a criticism is very far removed from the author's intention.
I do agree however that the title of the article (on HN) should probably simply be "Atomic John," it's okay for an article title to be a little bit mysterious, and using a subtitle creates a bit of the wrong impression in this case. (I am not sure about what the actual guideline is however)