The binding agreement we signed when applying for PNP only states that we have the intention to reside in the province, but intention is a very ambiguous word as it can change all the time.
If the binding agreement specifically says that all the nominees have to stay a minimum [insert a number from 1 to 999] years in the province, then that will be the end of this discussion. It should be just as simple as adding a sentence but why CIC didn't do so?
In my opinion, it is reasonable to revoke someone's PR status if that person landed right in a different province and was never going to reside at the nominating province.
It is also reasonable to revoke someone's PR status if that person left the province immediately or after a very short period of stay (say a month or two).
However it is NOT reasonable to revoke someone's PR status if that person has shown the intention by residing in the province for a long period of time, for example, 1 or 2 years or more.
Another way to look at it is that if you go to the CIC website now and see what you need for renewing PR card and/or applying citizenship, nowhere you will find about the constrains on the inter-provincial mobility for PNP nominee. If there is any, it should be clearly stated out as it should affect greatly on lots of people.