This is merely speculative. but maybe a more useful metric (rather than counting the number of syllables stuttered) is to measure the duration in which the execution threshold was too high.. to release the speech motor plan for overt execution.. so for isntance, if the execution threshold was too high - for a total of 30 seconds, then it will effectively resolve the issue, regardless of whether it involved 50 repetitions or a single block (or inhibition of motor plan execution)