Personally....what is a cast? It is the rod correcting itself or straightening after energy applied has made it bend. The speed in which this correction is made will determine what speed the sinker will be sent out. Slower rod = slower sinker speed meaning small cast and vice versa. Aerodynamics plays a part when we look at the air turbulence created by the sinker bait etc.... But to get distance it comes down to that rod straightening. I have several rods to choose from but always like a rod that is capable of a distance cast. This is what determines what I look for in a new rod and what I will buy. A good fisherman can bring in a fish using any rod. Thats where skill becomes the game maker.