With my bike the slower use of the throttle is barely perceptible. I just don't whack it open real quick. I any case, you don't usually do that when you are racing. You are too busy being smooth. I don't think I have ever opened the throttle quick enough for the lack of vacuum to cause a gasp. With the small ports, it is pretty impossible, even though I use 6D Mikuni needles, which are the slowest taper. Throttle response is usually pretty poor because of the heavy crank anyway. The slower taper needles improve it.
