[MT930]

I've heard the old timers talk about it in Alaska in the winter

I bet the procedure needed to be followed carefully, not to much fuel.

I bet you wanted it to evaporate off before selecting higher power settings, Had to effect engine life in a negative way.

If you had a lot of Oil / Fuel seepage in the lower cylinders on the big round engines would it blow jugs off starting them ?

The practice makes sense to lower the viscosity, it just sounds crazy to add fuel to the oil. 50 Wt oil is like peanut butter at -10F

Unbelievable what you can learn here.