MacNaughton is an old-school Liberal, well-respected within backroom circles. He's pretty tight with Trudeau's Chief of Staff, too.
As is his wife, Leslie Noble. It might seem funny, but while I learned a good deal about how the system functions (and doesn't function) from David, Leslie was far more of a mentor - I learned a good deal about how to work the system from her.
One's tight with the Liberals. The other is tight with the Conservatives. Both know how to speak to elites on either side of the spectrum. And both are tight with key folk in the PMO.
Think about the back-channel potentials in this for a second. Think about the influence the PMO theoretically could have for nudging domestic partisans and for building bridges or at least framing issues in a positive way south of the border.
Then, throw Open Government into the mix. The people behind that on both sides of the border are collegial, too.
Interest dynamic, is all. And one worth paying attention to.