Yes, this will be a problem. Make sure your position title matches a NAFTA classification *exactly*. While processing my last TN, the customs agent told me he rejected someone's TN application because he couldn't tell if the title in his offer letter was the same as the one in the NAFTA rules.
I believe many are looking for any excuse to reject a TN now, but disregarding that -- look at it from their perspective. How are they supposed to know if a Statistical Programmer is the same as a Mathematician? Sticking the title at the end looks suspect. Keep it simple for them.
"Mr. Rizzo has clarified it very well."
With respect to Mr. Rizzo, he is wrong. I have read the rules and they were explained to me by a customs agent and two different sets of immigration lawyers. I'm also going by several years of personal experience and stories of others.
Saying "the motive is to earn extra legal fees", well, what business is Mr. Rizzo in? Isn't his motive just as suspect?
(1) You can't go directly from TN to green card. Applying for TN status implies you have no intent to stick around. If after a couple of years you want to get a green card, you are going against the intent of TN.
There are two independent tracks: H1B -> green card, and TN -> TN. The second track was never intended to supplant the first.
That being said, yes there is a way to go from TN -> green card. It is, my lawyer assures me, also perfectly legal. Talk to your lawyer. You didn't hear it from me.
Anyhow, it is *much* safer to start down track #1, if you can. Big businesses are pressuring the US government to increase the cap on H1B's (even Bill Gates has gotten into the act) so maybe there is some hope there.
(2) In the spirit of temporary status, you are supposed to maintain a Canadian residence. This is proof that you intend to move back to Canada. This rule is completely unreasonable, and for years they looked the other way on this one, but the times they are a-changing.
I got a major hassle last year and one of my colleagues got a bigger hassle this year. She was denied entry for a few days while our lawyers hashed it out.
My wife's lawyers usually renew her TN by mail. It seems by far to be the safest option. It saves you from the stress at the border and if you are denied, at least you aren't stuck at the airport.
Some people get lucky at the border and have no trouble. Some people are unlucky. The border crossing as well seems to make a difference. Ironically, the borders that see a lot of TN's seem to be the worst. My wife renewed in Chicago two years ago after coming back from Australia and had no problems.
It's a crapshoot. How long can you roll the dice and keep getting sevens?
Another thought: Clinton, Obama, and McCain promising to revisit NAFTA. They are talking mostly about Mexico, but US automakers moved some plants to Canada too.
So stay off the TN treadmill if you can. Before I jumped on it, I didn't know any better and neither did my company. TNs are made for short term employment and many customs agents are now pushing that fact.
Next time I get a hassle from a US customs agent, I might try saying "look buster, I pay your salary" but that's just not the Canadian way.




