Well... here's another fine mess you've gotten us into ollie. I don't think there is any scientific proof to any of this and it is very sporadic. Like the op I have a weed wacker and mowers that I never do anything special to for winter, and I leave gas in them and have never done anything to the carbs and they always start in the spring. I live in the heart of farm country and YES ethanol has driven up the corn prices dramaticlly and is forcing the small family farmers out of business and I can buy pure gas at my local station and Iget 10% better gas mileage. I all I know is whatI see and what Iexperience, your results may vary