I read this story and it struck me as suspicious for the same reason. Peter Roberts (an immigration attorney) commented on it here a few days ago:
> That's extraordinarily unusual and in my experience has only happened when CBP believes that the applicant was lying or has a criminal record so I wouldn't base the decision on where/how to apply on this very low risk. Depending on the TN application, there are better and worse ways to apply for a TN and from an outcome standpoint, sometimes it's better to apply with CBP at the border or with CBP at a U.S. airport by flying directly to the U.S.
> That's extraordinarily unusual and in my experience has only happened when CBP believes that the applicant was lying or has a criminal record so I wouldn't base the decision on where/how to apply on this very low risk. Depending on the TN application, there are better and worse ways to apply for a TN and from an outcome standpoint, sometimes it's better to apply with CBP at the border or with CBP at a U.S. airport by flying directly to the U.S.
https://news.ycombinator.com/item?id=43363854