The field tests for acetone may be confounded a bit by the change to low sulphur fuel that's going on. note that LSDF has according to wiki article, less bang and lower lubricating quality - this would seem to offer slightly higher fuel consumption. If the acetone works and lowers consumption, the gain might be masked by the change in fuel - worse, if damage occurs it may be due to the fuel sand not to acetone. excerpt:
"Sulfur is not a lubricant, however the process used to reduce the Sulfur also reduces the fuel's lubricating properties. Lubricity is a measure of the fuel's ability to lubricate and protect the various parts of the engine's fuel injection system from wear. The processing required to reduce sulfur to 15 ppm also removes naturally-occurring lubricity agents in diesel fuel. To manage this change ASTM International (formerly the American Society for Testing and Materials) adopted the lubricity specification defined in ASTM D975 for all diesel fuels and this standard went into effect January 1, 2005. [4]
The refining process that removes the sulfur also reduces the aromatic content and density of the fuel, resulting in a minor decrease in the energy content, by about 1%. This decrease in energy content may result in reduced peak power and fuel economy. The reduction is only slight and will likely go unnoticed.
ULSD will run in any engine designed for the ASTM D-975 diesel fuels."