well, you are correct that a shorter intake port helps produce higher peak power numbers at the expense of some mid and lower rpm power.
Velocity stacks come in different heights, and thus serve two purposes. A. Smooth the flow of air into the intake tract, B. Manipulate the power curve.
Check any Busa or newer 6R and you will see that there are two short stacks and two longer stacks. I know of a GSXR1000 owner, and some Busa owners that went to all shorties to try to increase peak power.
I don't know how much power we're talking about here, it's probably only 2-5 at best, but every little bit adds up!
"<font color=blue>How about never, is never good for you??</font color=blue>"