Yes from June '67 to July '68. But as you said, he doesn't talk about it much, nor was there much in his book about that time. However the quotes above are from the "Kerry Page" on the USS Gridley site Needless to say his shipmates were not overly impressed, especially the enlisted, nor are they happy about his activities upon his return from Vietnam. Strangely enough, they think he lies the same way the SwiftVets do.
or is this something that came over him suddenly when he realized that war hero's didn't play well in Massachusetts politics?