From Xavier Averso himself :
this rotor was not for a gyro use, it was a special order fom a customer.
he took 3 shortened blades (2.80m) he put on a tri-bladed hub some guys were doing, this hub had no lead-lag hinges.
results : long take off (small diameter) , high command efforts, better high speed and finesse (lower disk pitch).
he stopped the test to not damage the blades.