Anytime I see something like this in a catelog I question it. It sounds like he is trying to give a little push to a certain product, there's always a business side to it!

Like others have said if you knock off 15-30 grains off of your arrow you can expect it to shoot faster. Thats why a lot of people started shooting smaller vanes with small mechanical heads. They fly like darts & they pick up a few FPS as well. I have shot a mixture of vanes sizes & feathers. I still think 4" vanes group better with most broadheads and are a better choice for most hunters especially if they are using fixed blade heads. If you are shooting an ultra short & small head like the Rocket Steelhead then you can expect great flight using a smaller vane.

It' all relative, really.