factual error- work visas are NOT granted to Canadians unconditionally. The terms under which a TN visa can be granted are painstakingly spelled out under NAFTA (I read the whole treaty and it gave me a headache for 3 days.) Only certain categories of professionals are covered, they must have a certain minimum level of experience, at least at Bachelors degree in an appropriate field, etc. My company has hired several Canadians for high-tech jobs. Several got rejected for the visa, either because they did not meet one of the criteria spelled out in the treaty, or because some officious immigration bureaucrat was having a bad day and decided to toast their nether-regions.
Ouch! I've always wondered about NAFTA. Why does it take a document the size of a phone book to say "free trade"?