I am playing the AMT Red regular shafts in my irons and prefer the constant weighting in the XP 90 regular. I am looking for the highest launching lowest spinning shaft. The butt frequency in the XP 90 seems higher than the AMT Red which is going to make it feel a little stiffer. Can I soft step the XP 90 for a little softer feel and to get an even higher launch without creating too much spin?