The article you linked said roses need the nutrients stored in the branches for nutrition over the winter. I wonder what kind of nutrients they are talking about? And if this can be substituted by feeding the roses lightly?
Also, the article said if the roses are kept covered, shutting out light, it will discourage growth over the brief warm periods during winter.
It's tempting to try covering them with burlap and straw, since they are cut down so low.
Do you have snow cover all winter?
I'm pretty sure I have pruned mine in the fall, and that didn't kill them.