I'm no engineer. I do contemplate their how and why in things they do. In the case of my 96 Camry 4 cyl. , there's a heat exchanger with coolant cycling through it installed between the oil filter and the engine block. The 2 fluids share temperature. These engines typically reach 300K + miles with a percentage surpassing 1/2 million miles.
My take on this is , first , the cooling lines in the rad. are too small ! Second, why don`t u just wrap the header in that location, and wrap the oil filter itself. I have been wrapping my starters for yrs ! Have never lost one yet .