What Limits
Such things are defined by each NAA in some way and this is not an attempt to apply a global standard but to test the effectiveness, or perceived effectiveness, of each licensing/proficiency management system.
If it is shown that the real world experience indicates that despite a good-looking set of regulations the end product is not producing a satisfactory level of competency within a national grouping of pilots - even if some companies within that grouping have acceptable levels - then we must look for some other mechanism for ensuring sufficient competency. Maybe OGP and its affiliates can help? If customers are made aware of any systemic shortcomings (on what may be a global scale) then maybe they will have the clout to change some priorities that will allow sufficient training and proper screening based on competency.
More answers to my original questions are required to even begin to make some sort of assessment. One thing is for sure, helicopters are getting more sophisticated and complex and therefore ever less tolerant of incompetence.
G.