Many people don't have a heater so this is not an issue. Many ask about making their
oil cooler functional, should they or not, well in FL reducing heat is the main concern. I really don't need an
oil cooler on the street, so I turn my
oil cooler in to another radiator by running in the warm weather the heater lines to it. When I need heat, I reconnect them to the heater. On a Daytona which has a large oil cooler you pick up an additional 10-15% cooling capacity by running your heater water thru the cooler. If I saw temperatures in the oil that warranted it, I would reconnect the oil cooler as an oil cooler but I don't. Just a thought.
Bill K