Both Daddio and Durbanic are “spot-on” with their advice.
The only time we ever heat a fat system (mind you, I said “fat system” not oil) is when we are adding a solid fat such as butter, margarine, shortening, or lard and need to deliver it to the mixer by means of pumping it. In that case we will heat the fat to a point where it is liquid so it can easily be pumped from the storage tank to the mixer. In many instances the fat is received in tank cars already heated so it can be transferred to the holding tanks, the holding tanks are heated to retain the fat as a liquid, the lines through which the fat is pumped are also heated to prevent solidification in the lines. When a solid fat is added to the dough in this manner it must be treated in the same manner as an oil would.
Outside of that, there is absolutely no benefit to heating an oil or solid fat.
Tom Lehmann/The Dough Doctor