On second thoughts, even though YE #1 is a priority, Fed is likely to skip Montreal in order to improve his chances at USO. If the gamble
works, the fact that he skipped wouldn't matter. If the gamble does not work, he can always throw in an extra tournament like Tokyo 500 etc, after USO , if needed to boost up the points.
Actually, here is direct answer from Fed himself about the schedule.
Q. You said you're not looking too far ahead. In terms of this season with how things have gone, do you perhaps now reassess your goals in a different way, whatever goals you had before, and maybe change them?
ROGER FEDERER: "I don't think so. I was always going to play more the second part of the season. I wasn't going to skip entire swings. I wasn't going to skip Asia, the American tour, whatever it was, the European indoors. I was always going to play as much as I possibly could. So I think I'm going to stay true to that.
Now we have to sit down tomorrow and decide what we're going to do with Canada or not. But most likely I'll definitely play Cincinnati and the US Open, Laver Cup, Shanghai, then go back to the indoors. That's the plan for now."
So, it looks like they are leaning towards dropping Canada. Even though the word tomorrow is used in the answer, do not expect any immediate decision. This is because Fed is already entered in Montreal. So, he does not have to make any decision in a hurry. He can always withdraw from Montreal without any penalty. If he is withdrawing, he will definitely withdraw before the qualifying tourney for Montreal starts, so that the person next in line can get direct entry and so that the draw does not become imbalanced. That gives them more than two weeks time to mull over the issue and make a decision.