SweatHog said:Have a friend who got his Initial seaplane rating in a complex twin. He had his own Grumman Widgeon. Does a MES qualify you to fly SES without further training?...or is it just a formality to get the SES?
NO and NO. It would be an additional rating. It is not unknown as many military pilots do the conversion and end up with a Commercial MEL. Then they will do a SEL add-on. I have seen one or two fail this checkride. Usually because the examiner feels their additude that the little airplane will not hurt them is dangerous and fails them.