Spin strakes were not required on Oz Tigers or Chipmunks, never had issues spinning either myself. Some were of the opinion that the Chippy earned an unsavory reputation because of the length of time it took to recover, instead of waiting for the recovery action to take effect folk would become alarmed that recovery was taking too long and then start trying alternative methods - which would not work. The Tiger spin was rather benign I thought and used to enjoy it, anyone with an insight into why strakes were fitted?