A little something that interested me years ago along the lines of this topic. I think Nick can elaborate.
For many years the Cobra used the same old rotor system a six inch cross section of the blade near the hub (24 inch chord?) weighed in at about 15 Lbs, maybe more. Then along came the Kaman composite blades with a (28 inch chord?) That same six inch cross section weighed in at about 3or 4 lbs. The difference of the total weight of the new blades had an amazing result in the aerodynamics. So much so that Emergency procedures differed for the aircraft depending on which blades were aboard. Those lighter blades made a real difference during a needle split. You had better be on it quick or you were into low rotor RPM right now.