Well did Jon say "4 countries" at the final pitstop?
I don't see a problem with that.
Wikipedia defines a "country" as
A country is a region identified as a distinct entity in political geography. A country may be an independent sovereign state or one that is occupied by another state, as a non-sovereign or formerly sovereign political division, or a geographic region associated with sets of previously independent or differently associated peoples with distinct political characteristics.
So its not out unreasonable to classify Macau and Hong Kong as countries!
So I could say Texas is a country and P.E.I is one too.
Hong Kong is an SAR, which is not comparable to Texas or PEI, because they are comparable to Guangdong or Jiangsu.
But before Texas became a state of the US in 1845, it was a sovereign nation (The Republic of Texas, 1836-1845).
Plus, the SAR refers to a closer relationship than that between Scotland and England, for instance.
...your Texas argument is irrelevant because it's a state and does not have the same degree of autonomy as an autonomous republic would...such as the SAR
Also no SAR-PRC is different to Scotland-England, because Scotland-England share things like democracy and multiparty states, whereas the SAR-PRC, only one does. Unless you can prove otherwise, I call bs on that too.
Please peruse the definition of the word "country" provided by Wikipedia cited by Leafsfan. I define Texas as a country because it's concordant with the condition "as a non-sovereign or formerly sovereign political division."
Both Canada and the US are federal countries which I reckon every state has some certain autonomy, unlike unitary-government-type nations.
Pertaining to sharing the ethos of democracy, I don't see it in the definition, hence I don't think it has anything to do in defining a country.
P.S. Now the Wikipedia page of The Amazing Race Canada 2 says the number of the countries visited is 3. It's much safer to say in this way I guess.