Is that an educated opinion spindlecone? I have read extensive testing posted on environmental sites that suggest that it is actually a fairly good idea. The chemical properties of acetone really seem to be benificial to gasoline. Basically gasoline in liquid form has a very "hard to break" surface tension, and as a result does not atomize well. Mixing Acetone into the fuel breaks down the surface tension and makes it much easier to atomize.
In short though this thread was not posted to attract arguement about whether acetone works or not. I dont particularly care whether you or anyone else thinks it does or does not. All I would like to know in one post from each person who has tried it, and has documented their gas mileage what kind mileage they have been getting, and how much acetone they have been using.