Here's the thing, and it's not cynical at all. You cannot measure a change in fuel economy and then attribute it to one variable in real-world driving. It is literally impossible, I linked an article here once that detailed how it was impossible, one of the biggest things was that the energy density of gasoline varied by around 4% even at the same gas station. That article showed how you must start with standardized test fuel to even have a hope of determining a comparative value for fuel consumption outside a laboratory.
As for that additive, there are standardized ASTM tests that accurately measure fuel consumption and they control all variables except for the one under test. To date I have never, ever seen any additive company publish the results from those tests, have you? Does this one? Will they? Until that is done there is unfortunately no way to conclusively determine if there really is an effect or not. Sorry, you may or may not believe that but it is fact. Measuring something is one thing (and often the easiest thing) but attributing it to one variable is entirely another matter.
You may have 24 fill-ups but each one is different, and there's no way you will ever make them the same so you can attribute an observed change to the one isolated variable of the additive.
This may be true but if you have a long trend and it moves when a variable is changed then that is statistically significant. What is the variable? Outside temperature, wind, oil life, etc. I drive the same route repeatedly all year. I see a small but measurable change using the exxon diesel over the Loaf and Jug diesel. This change is about 20-30 miles per tank and repeatable. I believe that the exxon diesel has a better cetane rating. There is nothing to say that the free juice that he is adding doesn't account for the statistical change. That being said it is only anecdotal without double blinded/controlled and repeatable testing. Not gonna happen with someones personal vehicle. Mobil One repeatedly says through their advertisements, lately with Kevin Harvick on the television that their synthetic oils are better than non-synthetic and last longer than non-synthetic oils. Their available published specification sheets don't show this ASTM testing you are referencing. Does it mean they are lying?
"For those naysayers that don't believe, I've got 24 previous fillups logged with an average of 29.4mpg, with a low of 26.3 and a high of 32.5."
This variance alone shows that tanks of gas can have alot of difference even without an additive.
Exactly. Unfortunately unless you are measuring precisely to the ounce how much gas is going in during a fill up there is no way to know if the product helped or not. Just where the pump clicks off from one fill to the next can vary enough to skew the results considerably. Even with the same gas pump.
I routinely use at least one PEA based cleaner every 5k miles, and the last one was Redline SI-1 at about 4200 miles before the Hot Shot one. Anyways, that's been my experience so far, and if you're interested in trying something new, watch for when it's actually released to the market!
Lucky for you, all I ever get when using these PEA cleaners is a check engine light about my knock sensors.
If I read the story correctly, this lubricity fuel additive is not tested or approved. This guy (with the mystery box) is the guinea pig. So, while I am very happy to hear about the potential fuel economy gains, there are too many unanswered questions to get excited just yet. How much will it cost? Is it unknowingly damaging any other engine system? Has there been an emissions test to see what this additive is sending out the tailpipe? Is it adversely affecting the rubber components in the fuel system? How does it affect the octane rating of the fuel? Etc etc. I always like to wait and see how new technologies or new products work out in the long-term, instead of quickly jumping on the bandwagon of short-term gains.