foolish or not, I am not to judge.
If glow needs 18% oil, gas can do with a lot less because gas itself is a lubricant and methanol is not. 7% (1:15) to 10% (1:10) would be about right for bronze bushed connecting rods. The engine in the movie still was running very rich, so would get enough oil. Things change when leaned out properly and under full working load.