I think it’s supposed to make smaller, and hence better more efficiently burning, droplets............
Doesn’t 2 ounces or so of acetone per tank do the same?
Plus, it makes your injectors clean as a whistle!!
Sounds awfully similar to the controversial claims about using acetone as a fuel additive.
As a side note, I did my own little ad hoc "test" of acetone, back when gas was pushing $4.00 per gallon, in a Corolla. Three "cycles" of three tanks with (3 ounces per ten gallons), and three tanks without. Mileage with acetone averaged a little over 36. The effect, whatever it is, lingered through tanks without acetone, but slowly declined until the third tank without, which averaged a little under 32. Same daily commute, same driver.
I've since stopped using it, but have no doubt that there is something to it, providing close to a 15% increase in fuel economy. Engine ran better too, easier startup in a car known for hard starting, smoother, better pickup. Can't explain it at all, but that was my experience.