The benign effects of the financial crisis in Canada that reduced consumer borrowing in the US increased it here.  Low rates, but a healthy gap between funding levels for banks and prime rates meant huge profits form retail.  The banks pushed us all to borrow with slogans like "you are wealthier than you think".  I once heard a bank treasurer imply these spreads represented over 100% of their profits the prior year.

And so it is ironic that the banks are now among those heeding the debt level warnings.  There can be no explanation other than that they cannot wean themselves off it and need OSFI to help.  It is game theory run amok when an oligopoly needs someone outside the game to impel them to change the way they play.

With house prices up as much as they were over the year, even those that in a 250 basis point rises may have a little wiggle room.  I note that no one is estimating the price sensitivity of the real estate market to the move.  that would be a good piece of work.