While Coyne is attempting to deal with so-called "Sophisticated Theology," something the New Atheists don't do, even he doesn't get it. Plantinga is not trying to prove God, and the essay he's criticizing is from Plantinga's old school version. For a better critique read Jaco Gericke's Fundamentalism on Stilts. Yet Coyne is right when he says:
To paraphrase Orwell, one has to be a theologian to believe things like this: no ordinary man could be such a fool...It is apologetics: the practice of making stuff up post facto to buttress what you already know must be true. And, at bottom—and despite all the intellectual gymnastics of Dr. Plantinga—it all comes down to revelation, to what a particular group of people happens to find amenable as a "basic belief."