COC take less energy to penetrate. Pretty simple there.
The other thing is where do you draw the line? If 3 is better than 2...
That said more blades have been easier to tune and fly better, thats been true since I started this in the late 70s.
Correct!
3 and 4 blades both work well. Flight wise I don't see a lot of difference, I like 4 for the cutting.
Correct!
