I was not suggesting that the 1000 Metro and 500 jet should be a pilot's ONLY experience before being considered for command. Most operators also have a total flying time minimum of 3500 to 5000 hours, and should give credit towards the lower amount for pilots who have acquired experience within the organisation.
But I stand by what I say - having done B737 command upgrade training on several pilots with precisely the minimums I suggest - if the pilot is competent in the 1st place. If not, no argument, no upgrade. I have also come across pilots with 10,000 hours on type who were never going to make command.