Those videos are a bit misleading (IMHO). Automatic AF point selection - which is what iTR does - is not the same as AF tracking. I notice they don't take any photos to show you if the eye is actually in focus. Just because the AF point is over something doesn't mean it is in focus, especially if the subject and/or camera is moving.
One very useful feature that the Canon cameras have is that you can tailor the key AF parameters (including the AF point auto-switching sensitivity) to your subject. Who knows what they had that set to for the 'test'?
I believe iTR was developed primarily for sports photographers to assist in tracking individuals around the field of play and there are many other videos on YouTube showing that it does that very well.
My main interest is wildlife photography and I can think of very, very few situations where you would want to rely on automatic AF point selection and/or any form of facial recognition. A bird against a plain blue sky maybe but even then you will get better results using single point or one of the group/surround modes.
Having the AF point over the right place is a good start to getting a subject in focus. There's no point having fast, accurate AF on the wrong spot.
Not so much of an issue with sports, where the whole athlete is usually in focus, but more of an issue with wildlife.
When shooting moving wildlife, it's not easy keeping a single AF point on the eye at all times, especially if an animal is running and bobbing its head up and down. Maintaining a decent composition when doing so is even harder, if at all possible. If the AF system can lock on the eye and follow it as it moves throughout the frame, that's a huge advantage. I've got too many razor-sharp photos where the snout, ears, neck or (more often than not, for African animals who like to run away) bums are in focus but the eyes aren't.
