It's important to keep in mind that one isn't necessarily opposed to the other. However, we can see that high‑speed rail offers significant travel time gains over high‑frequency rail.
Earlier, someone compared the time it takes to travel by train and by car between their riding and Toronto or Ottawa. Personally, if I want to take the Roberval train to Montreal, it will take me 10 hours by train, but only four and a half hours by car. So you'll understand that, in my case, my behaviour wouldn't be changed by this investment because there would be no gain. That's what you have to consider if you want to maximize the use of the train: the speed of travel.