Thanks for the reference, PMM. I went to the CanLII website, and searched for “divorce and substantial connection”, as you advised. I did not read all the cases; the first (Bhatti v. Canada) seems to settle the issue clearly.
There is a lot of legal opining and argumentation in the case – I guess lawyers get paid by the word!

However, after blowing away all the legalistic dust, the crux of the matter seems to be that where a Canadian resident has a real and substantial connection with a foreign jurisdiction, for a year before obtaining a divorce in that foreign jurisdiction, then Canada will recognize the divorce. A year of residence is not the only ground for valid divorce.
The CIC Operations Manual mentions both criteria: residence and connection.
Quoting from the court transcript:
“The Operations Manual on which the visa officer relied, states that the parties must ordinarily reside in the foreign jurisdiction for one year before applying for a divorce
or the petitioner must have a real and substantial connection to the foreign jurisdiction for the one year period before divorce proceedings begin. (My emphasis.) The Operations Manual is not a statement of the law. Rather it is a guide and I find it more helpful to refer directly to the Divorce Act, the common law and the jurisprudence.”
And again:
“The Divorce Act requires that one of the parties be ordinarily resident for at least a one-year period before the start of divorce proceedings. I take the words “ordinarily resident” to mean where one’s every day life is centered and on the basis of being in Pakistan for one month in 1996, the appellant does not meet this criteria. However, the common-law concepts of “domicile” and “real and substantial connection” have not been displaced by the Divorce Act. This is implicit in a reading of sections 22(1) and (3). Indeed, in providing a guide for family law practitioners in Ontario when providing opinion letters about the recognition of foreign divorces, the Deputy Registrar of the Ministry of Consumer and Commercial Relations specifically refers to not only to subsection 22(1)
but to recognition on the basis of domicile and on the basis of a real and substantial connection between the party or parties and the granting jurisdiction.[26]”(My emphasis.)
In the court’s eyes, the man who divorced in Pakistan had such a “real and substantial connection” even though he was a Canadian citizen and had resided in Canada over 30 years. He was also a citizen of Pakistan, owned a house (inherited from his father), owned a small parcel of land, had committed to donating a large sum of money to a Pakistani religious school, and intended to retire in Pakistan.
So, apart from the uncertainty of leaving a subjective Visa Officer to determine whether one has a “real and substantial connection” with a foreign divorce jurisdiction, absent a full year of residence, this will do.