I repeat, it’s NOT a new rule, it’s just that INS has historically been extremely haphazard about enforcing the rules they already have. Especially on the Canadian border, people are routinely waved across with scarcely a glance at their documents, particularly if they are Canadian. AS I mentioned above, the student visa category has never been designed for part-time students, and the visitor visa category is incompatible with pursuing a course of study.
It’s unfortunate that it’s taken events like those the U.S. has experienced over the past few months to make the inspectors follow thier own rules, and it’s even more unfortunate that until recently there were only a couple hundred inspectors across the ENTIRE northern U.S. border.
We’ve given the inspectors a nearly impossible job, and the end result has been a big, fat mess, but one which I hope will soon have a regulatory fix and more resources thrown at it.