I recall one of the Holocaust survivors who refused to debate people who claimed the Holocaust never happened. When asked why, he said (and I am paraphrasing): "If you dignify nonsensical crap by debating it, one side will say one thing and the other will say the opposite, and most in the audience will conclude that the truth must lie somewhere in-between. Often the truth is not somewhere in-between: one side is completely correct and the other side is completely wrong."
One can make up any lie and get at least some people to doubt the actual truth. In fact one of the problems with most current journalism is the belief that good journalism requires that a reporter present both sides without taking a position, e.g. the flat Earthers and the astronomers, and let the public decide who is right.
Here this effect (the truth must be somewhere in-between) is even further embellished in the debate about the Swift Boat lies due to Sunmaster's willingness to speculate, completely in the absence of facts or evidence, how the Swift Boat events "probably" happened, his speculation that any errors in the Swift Boat campaign are due to differences in memory and not political prejudges, his proposal that personal income is the only basis behind people's motives, his perceived lack of a reason for someone's willingness to lie, etc. No facts, just Sunmaster "puzzling it out" within a strongly conservative political bent. Therefore the side with the evidence: the military-awarded medals from his superiors, the support of all but one of the people who crewed for Kerry (and he was not present during the actions for which Kerry received the medals) the written documentation from the era, the news investigations during the election period that proved Swift Boat Veteran statements were incorrect, is to be considered as having no more veracity than the people who were not there at those actions (all but one never ever even served on Kerry's boat), and were, decades later in a political campaign, coming out of the woodwork with little more than verbal vindictiveness. I would emphasize that none of these Swift Boat Veterans who criticized Kerry, including the one member of his crew who did disparage him, were there at the actual events for which he received his medals. In fact I believe that less than 1/10 of the total Swift Boat Veterans membership was even willing to participate in the statements made against Kerry.
Probably okay if used only to generate an argument on an Internet forum; more of a concern if the person advancing these made-up, vest sew on a button, speculations actually believes them himself.