It was a ridiculous promise to begin with. It would have been possible to bring in a ranked ballot or a two-round system which wouldn't have required a redrawing of riding boundaries but many forms of PR would have required redrawing of the ridings and possibly a change in the number of the seats, which would have been almost impossible to accommodate to that time frame. The election promise included PR as an option and didn't say anything about a PR system that doesn't require rejigging the ridings. The media should have been all over Trudeau on this promise but they were too busy licking his boots. And a week from now they will say it's just old news.