I couldn't find the author name on the page, but this choice of words seems to indicate that (s)he has a French background. "Insoluble" and "Déconfit" are french words, and "Insoluble" is a relatively common word.
The author's name is Ryan Avent. From his personal site, it looks like he's from the states and he got his MSc in London. As for discomfit and insoluble, those words strike me as being in line with the Economist's style.
