Diplomas - what are they good for?

I notice that there are people mentioning their School Vision Diploma as evidence of their specialism in paediatric optometry. Is there anyone else out there that has some reservations about this? I am not sure that a body set up as a personal pet project including areas based on anecdotal evidence and with litle transparency and no apparent plans to carry out evidence based research to back up some claims should be in a position to offer diplomas to be cited as professional qualification. Agree or argue?