In a nut shell, the 3F burns faster, you do have to reduce your charge weight 10%, but as Cayugad said, the amount of improvement you get may not be worth it. But try it and see what it does with your particular combination.

I have done this with Blackpowder and have not tried this with the substitutes out there, and I had/have a couple guns that love this stuff and that is what I shoot. The one gun that it didn't make a difference in was my Traditions 45 caliber with that darneded 1:20 twist barrel, once the powder charge peaks over 80 grains 2F or 70-75 grains 3F that is it, make accuracy is obtained. Good luck.