Someone correct me if Im wrong……when the Tiger was released into civil service and given a standard cat certificate of airworthiness the CAA took it as is and certified it (anti spin strakes and all, which were fitted to improve spin recovery when bomb racks were fitted).
This was not the case when the were released in NZ and Australia.
As it stands it makes virtually no difference at all to the spin or spin recovery characteristics of the aircraft, having flown both.
You will also note when looking at a number of NZ Tigers that they dont have slats, again it doesnt make a great difference to the aircraft.

…..Waiting to be shot down…….