He's not refuting "X", he's refuting the claim that "studies have shown X". To do that you don't need to run your own studies and show different results from X — in fact "X" might even be true. But if the existing studies don't exist, or can be shown to be flawed, then it's perfectly valid to simply point out the holes.
Your debugging criticism is somewhat valid, but the context here in that the original Sackman paper was mostly testing the difference between "online" and "offline" programming (i.e. programming whilst sitting at a computer or not — nothing to do with the internet!): see, for example, http://dustyvolumes.com/archives/497 and http://dustyvolumes.com/archives/500
The research was on whether debugging whilst sitting at a computer would make you more lazy, which is an interesting experiment for its time, but isn't really that connected to the modern concepts of debugging vs programming.
But to me that's like saying no study has proven global warming is real. Because study X only measured ice cores in Antarctica. And study Y only measured tree rings in the amazon.
A far better refutation would be be: Well I ran study Z, and it shows...
(Not that I think the article's claims are as outlandish ad Global Warming Deniers, or that developer productivity has been studied nearly as much as global warming.)
Your debugging criticism is somewhat valid, but the context here in that the original Sackman paper was mostly testing the difference between "online" and "offline" programming (i.e. programming whilst sitting at a computer or not — nothing to do with the internet!): see, for example, http://dustyvolumes.com/archives/497 and http://dustyvolumes.com/archives/500
The research was on whether debugging whilst sitting at a computer would make you more lazy, which is an interesting experiment for its time, but isn't really that connected to the modern concepts of debugging vs programming.