Based on my personal experience, Kerry received his Honorable Discharge under the standard process, which obtains for naval officers transitioning through the Reserve process.
kabar's statement does not include a "probably" or a "possibly," which means that he makes the appearance of asserting instead of making an estimate ... but, let us say that his is making an estimate.
He may be correct in his estimate, but the odds are very strong, that Lt. Kerry's route to the point at which the tradition voluntary and/or involuntary processes began for both officers, to certificate of Honorable Discharge, was NOT the path taken by kabar's career.
kabar has difficulty fathoming that probability.
The odds are very high that Lt. Kerry's career (again, his records and activities) were subject to more than one investigation and/or administrative review for cause, that being, again, Lt. Kerry's associations with the avowed enemies of the United States.
Given that probability, the issue is not really so much that Lt. Kerry was at some time between 1972 and 1978 given a certificate of less than Honorable Discharge, but, that Lt. Kerry was the subject of some kinds of investigation that placed his status in a lesser light than kabar's. So much so, that Lt. Kerry was effectively in some "pool" wherein were other officers who may have had various colored wartime and post-active duty transgressions in varying levels of not serious to very serious.
For which probability, there is much speculation but almost no documents that have yet come to light.
kabar did not address the reissue of sKerry's medals at the same time as the board of officers issued the discharge. This would have not been required if they had not been revoked by some prior DOD action--such as a DD or a BCD.