One of the largest flaws in this idea is that the VAFC really isn't a true "Power" tuning device. It's mearly something to get your A/F's in a safe range for modified vehicles. Yes there will be some HP gains in running a little leaner than on the rich side, but all decent tuners know the power comes from timing which the AFC will not be able to alter. As someone stated above, it will depend on who has the best running conditions, without heat soak, many runs before etc. There is only so much you can do with an AFC for power and you may have ten people with the same top HP. Most people will melt the engine thinking running it leaner will get them more power than the last guy.