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Yes, both Nate Silver and Nate Cohn (the latter from NYT) have criticized USC/Dornsife poll. Nate Cohn’s critique concerned a couple of things, correction for small groups (that's were the lone Afro-American 19 year old guy from Illinois came in), but what the Nates were really upset with was the fact that USC/Dornsife corrected for the question how people voted last time. Unless many other polls this poll was not happy with samples where you had a 10% advantage for Obama vs Romney.

In an article that was published a few days after Nate Cohn’s NYT piece one of the persons responsible for the USC poll wrote a reply. He claimed that they did not see much difference whether they corrected for the results of last election or not. It was not quite clear from that article whether USC had decided to remove that correction from their methods or not, but it is a fact that from that day on the poll tightened considerably, and Trump has never had above 6% AA support since then.