What is the difference between the 325 MPG CITY file, and the 325 MPG BoostFooling file?

It says the city file has slightly more timing, which makes sense. But, what does boost fooling do for milage, and how does it work?

 

If I'm correct on this the bf doesn't do much it's just that there were a few complaints that the fuel milage turns did not use bf so they added it in to try and make some people happy. Me I think it smooth's out they power band but would not say it makes it more powerfull or mpg better. Just seems on my truck a tick smoother running. It's just like putting on a bf on a stock truck,are you going to gain better mpgs probly not but it will feel differant. Just my thoughts and exsperance.