Isn't it true that a Mexican citizen with a valid TN visa may be admitted to the United States in TN status for up to three years, provided that the individual’s passport will remain valid throughout this period and the individual is otherwise admissible?

Assuming that the Mexican citizen holds a passport that is valid for at least three years and that the alien is otherwise admissible, isn't it true that an employer’s letter or statement confirming that the employer intends to employ the alien for a temporary period of up to three years is sufficient to support admission for the requested period of time.

For a CBP port of entry, what is the procedure available to seek supervisory review of an officer’s refusal to admit a citizen of Mexico to the U.S. for the period of offered employment up to three years?

Isn't it true that, in determining whether the offered job comes within a NAFTA covered occupation, CBP Officers must evaluate the job duties as described in the employer’s statement supporting the application for admission and that the job title alone does control the determination?

Would an engineer with the job title of sales engineer or engineering manager be approved for TN classification if the job duties will require the application of engineering principles in support and promotion of technical products?