Ah this is interesting for a teetotaler! I did not know it was desirable to keep the whiskey warm. I thought, like soft drinks, the idea was to keep it as chilled as possible. So the optimum temp is just a little below room?
Room temperature on a cool day is what many will say is the 'right' temperature, but there is no right or wrong, despite what many questionable experts will tell you.
Nobody is going to agree that X is the best temperature for every whiskey. Whiskies and drinkers are all different. Room temperature whiskey and ice give the most control with the least complication.