Okay, but he's basing this argument on his paper, where he sets out to show that immigrants are in fact, not exceptional. However, if you believe my reasoning,

Okay, but he's basing this argument on his paper, where he sets out to show that immigrants are in fact, not exceptional. However, if you believe my reasoning, then he isn't really measuring anything. So, we don't know if immigrants are exceptional or ordinary or worse. Or at least not based on his paper.