Sorry about that. I don't think there is enough hose to make a difference in the hydraulic oil temp. But if you have seen a difference in temp between hoses that are covered and those that are not who am I to argue.
My JD with Parker hoses is about 12 years old, 6000hrs and seldom gets parked in the shade. Very seldom do I have to replace a hose unless it has been damaged...
I have older wood splitters that also have old hoses. Maybe we just don't get enough sun....