Dynamic except for paddles and tail blades but they do get weighed and matched to 1/100th of a gram. It's the hoola-hoop factor. Do you want your disc spinning like that or smooth as you can get it. If the CG in the baldes are at different location in the span, the masses will be different and will try to stretch out and wobble the disc off center and fight against each other which causes vibration on the main axis. Balance is balance. You may not notice it with a smaller blade but on it's level, it is vibing and vibing is bad for helicopters, linkages, bearings etc. The smoother you can get the balance the longer things will last and the smoother your helicopter wil fly, period.