Wouter,
What I mean is that redius of gyration is the conventional name for resistance of a mass from rotating. If you take a long slender object such as a mast and reduce the weight by half it should cut this property by about 4 (or is it 8??). An aluminum T mast weighs 38 lbs and a carbon version can weigh 21 lbs. The overall radius if gytation of the entire boat is the summation of it's various parts. These can be combined by superposition just like the linear motion analogy (moments of inertia). So a carbon mast may help the boat overall by say 8% (a wild guess). The boat radius of gyration is directly related to the amount of energy it takes to move a boat through waves (reduces pitching moment and rolling moment). Does it make sense now?
