Manifold heat cross over physics and benifits

Sooner or later, I will pull my drive train to paint my car. When I do I will repaint the engine especially because the heat riser passage has burned the paint off the intake. At that time I will disable the valve and block off the passage to the intake. Most of us don't drive our cars in the cold weather and most of us start our cars up and warm up the engine before we take off for a drive. The heat riser system really isn't needed under these conditions. tmm