My first read through, I didn't even notice that he was accusing metformin of shoving glucose into the liver etc... I think maybe the reason I didn't notice is that this is such a "well oiled groove," he's said much the same things about insulin a zillion times. That might be the problem, this basic theme being so well travelled by both him and his readers that nobody noticed its misuse when applied to metformin. And thus the brain fart.