Oh, come on. 2017, playing Montreal was a bad choice. Now not playing it was? What would have been gained?
There is some element of truth in what he says.
Players can only decide on how many tourneys they play and not on how many matches they play. The nice thing about playing in Montreal is that if you go deep and think you got enough match practice, you can skip Cincy (as someone did) and on the other hand, if you go out early, you can always play Cincy to get sufficient match practice.
This year there is an added value in playing in Montreal for Fed (as I already elaborated in another post before Montreal started perhaps in this thread). With Novak not playing, if Fed can stop Ralph in Montreal, that will be a huge swing and will get him #2 ranking temporarily and that #2 could possibly even stick with him for USO, getting him a good placement in the draw.
In 2017 also, playing Montreal was not really a bad choice. It was playing there without proper practice and getting there straight from some vacation with Mirka somewhere.
The bad thing in playing in Montreal is that, if you do really want to practice, you need to get to work at least a week before that. That basically gives you exactly two weeks of rest after Wimbledon. That is too short of a break, especially considering he played on Clay this year.