Good article and timely observation.  That's assuming Mr. Trump and his team even know about FTA and its genesis predating NAFTA. 
The reality is that the bulk of cost savings that various US manufactures (particularly auto makers) have enjoyed through the life of NAFTA is predominantly based on labor costs.  Indeed, it is the astronomical Canadian taxation that provides for such things as legislated employee benefits, far lower employee health care costs for the employer, and of course the lower dollar doesn't hurt.
What is not commonly known is that the majority of the parts used in Canadian built vehicles continue to flow from the US parts suppliers. 
I think it would be a very interesting exercise for Canada to initiate the tearing up process of NAFTA and try to somehow use FTA as the fallback position as suggested by the writer.
Perhaps we can also begin a populist movement toward lowering Canada's outrageous tax rates!