My DD has been pitching with a four-seam fastball grip for about one year. Her PC suggested that she also learn to pitch with the two-seam grip (fingers with the narrows instead of across the seam "C") in order for the ball to either run in to the batter or out, depending on the grip pressure at release. What is your experience with the two-seam grip, is it an effective pitch and should you alternate back and forth the different fastball grips during the game?. One of my concerns is that she has experimented with the two-seamer and the pitch is not as fast, at least right now.