Deforming the core of a bullet and deforming the jacket will change the center of gravity. As that bullet rotates, with a center of gravity now outside the center of rotation, this will add inaccuracy.
You can crimp or not crimp based on what works best for YOU.
It would appear that the writter of this quote does not take into account what the heat of the powder does to the bullet in the chamber and barrel, yep, 35,000 to 60,000 psi has no effect on the bullet. If you could stop and check the bullet at the end of the barrel just as the bullet comes out you will see no crimp marks, the bullet has been compressed into the shape and diamiter of your bore with rifle groves (melted into shape).
So crimp away and it will give you a complete burn and faster fps.