Sure beats building a fire under it. I have block heaters in all my main tractors.
20 years ago we got hit with several feet of snow. I had to fire up the old Cletrac. We ended up building a wood & coal fire under it to get the oil thinned up so that we could get it moving. Once it moved ten feet, we had no problem.
If you are running propane, it is a must to have a block heater.