I agree with the flight idle position. the fLM is not 100% clear, but as said before if you read the whole procedure you do find yourselve in flight idle before the check is asked for. I have seen some pilots who do the ACCU TEST until the accumulator runs down and the control goes hard for some reason or others do big movements on the cyclic instead of the 10% travel asked. If you are at ground idle the starflex and spherical bearing is not offloaded by centrifugal force and in my opinion if you do the above you are overloading both in a situation they are not designed to handle.