I was not quite comprehensive enough about compatibility cheks.
I should have added "for methanol fuels and synthetic oil mixed gas". The matter is very complicated.

The amount to be mixed in is as per instruction on the bottle.

Indeed fuels are evolving rapidly, and the oxigenated stuff sold nowadays has increased cleaning capabilities, as well as the power to absorb a little water that has found it's way into the carb. With too much water, the oxygenators will separate from the fuel, and cause trouble.