Since the time when the 'issue' arose with the riders mentioned the conversion rate had been altered from 0.5 to 0.6 to attempt to rebalance the inter league strengths.
Then to combat the skewed format a further change has been made this winter.
Therefore IMO the MPT rule is outdated. However it is there and has been rightly administered and too late to change now even if the will was there to do so.