It's easy - Think of the boat and it's crew as a squad, and several of the boats make up a platoon. You operate alone, and with the otehr squads. Did the guys in the other squads still serve with you? Able to see how you operated, led, commanded, etc...? I'd think that would be yes.
Just because they were not on the same 6-man boat doesn't mean they didn't interact on missions, and live, and serve with John Kerry.
Okee-dokey! I just got a quick education in swift boat manning. Thank you, all. (20 slaps on my stomach with a wet trout for me!)