Please thank your dad, from this coastie, for his service. That was my understanding of the etiquette as well, but it's "misabused" often. I would never criticize someone for saluting servicemen, however, as a sign of respect.
I do not feel JFKerry was doing this to show repsect, but as a false way to attempt to earn respect. I agree it was poorly executed, as well.
Kudos to your Dad. Another coastie, Eddie Albert, not only offloaded Marines at Tarawa, but cruised around UNDER FIRE, picking up Marines wading into the beach and taking them in as well. Coasties got guts aplenty in my book.