Your understanding is not consistent at all with the government census stats. French only at home: 56%. English only at home: ~10%. French mainly + other climbs higher.

http://www12.statcan.gc.ca/census-recensement/2011/as-sa/98-...

It also doesn't seem true that Allophones (born not speaking English or French) necessarily are using English the most as their 2nd language. Allophones using French most often at home is increasing over time.

http://www12.statcan.ca/english/census01/Products/Analytic/c...

Going outside Montreal will yield 90%+ French speakers.

I would also offer my anecdote to the statistics that Tiktaalik provided based on a few trips to Montreal and French Canada over the last couple years--while it's true that many people speak English as well as French, English seems to be popular because of the large number of English speaking tourists that visit the city (in no small part because of its French culture). Even in the touristy areas you're greated with "Bonjour-hello" to see how you choose to respond. There were a few times I've been grateful to have some background in French, as the person I was talking to didn't know any English (this however, was mostly on the outskirts of Montreal and in smaller towns). Overall, I was surprised at how francophone the city/region as a whole were, as before traveling I had anticipated it being equally French and English.

Maybe that was true in 1965, but it's nowhere near the case today.

Historically the downtown business core of Montréal was Anglophone while the poorer, rural areas were completely Francophone. However, rural people could still vote: the result was the 1976 provincial victory for the Parti Québécois who immediately introduced far-reaching legislation requiring the use of French in public places, in the workplace, etc. The effect of this was to make Toronto Canada's primary business center.

There are still some English areas, I think mostly around McGill. Most of the city is completely French though.

As an English-speaker with only a rudimentary knowledge of French, I found Paris a lot easier than Montréal to get around in. In Paris, as long as you can remember to start with a nice "Bonjour"/"Bon soir" everyone I spoke with was happy to help in English as best they could. In Montréal, language is so politicized that doesn't work. To be fair, once people found out I wasn't from Canada they would be friendly and helpful -- their first assumption, though, would be that I was probably just someone from Ontario, must have had some French in school, and now am just refusing to try.