A great many arguments around here start because someone fails to accept that another's person's stated experience is plausible. As a social convention (as opposed to a matter of sheer logic) I think it is more important to cut folks some slack in such a forum, rather than less.
Out of curiosity, IYHO, does that cut both ways? Should you also be willing to cut an equal amount of slack for someone's skepticism? Would you claim that your own posting habits bear out the assertions you just made?
This, has been covered a bit by prior points in the thread (like the "Never Give Up, Never Surrender". But I will grant you that sometimes you do find yourself defending against A when A was never one of your points - largely because that is happening right now.

If you want to make that claim, you may feel free to do so. I, however, do not feel an obligation to therefore agree that it applies.
Aliens, the Loch Ness Monster, and Bigfoot make great reductio ad absurdumtype arguments, showing flaws in the logic at extremes, and thus calling it into question for many cases.
OK, imagine that you are on the Monty Haul TV show. You know that there is a small amount of money behind one door, a car behind another, and behind the third a goat. You've selected one of three doors, and do not know what's behind it. Monty knows what's behind all of the doors. Monty then opens another door, revealing the small amount of money. The question is, to have the best odds of winning the car, do you switch doors, or keep the door you originally had?
The answer is, you switch doors. The odds of you having picked the right door are 1 in 3, and the odds of the switched door being right are 2 in 3.
Now, the fact is that quite a few people -- even well educated people -- fail to grasp this. It seems as though the odds should be 50/50.
If you use a more extreme example, however, the logical problems become clear.
For example, if there are 1 million doors, and you select one, and Monty opens all but the one you selected and the one other, revealing no car, the odds are only 1 in a million that you selected the right door. Because Monty knows what is behind every door, he can open doors without changing the odds at all, so long as he doesn't open the door with the car behind it. Chance is not involved with the doors Monty is opening.
Given that extreme example, most people can see the flaw in the initial logic that led them to believe that the odds were 50/50 in the first example.
The problem is that twice before (third time's a charm?) I have limited the context to talking about RPGs. Whether or not the logic applies to Bigfoot sightings really isn't an issue, because these aren't Bigfoot forums.
The logic you are attempting to use to determine the plausibility of foo is not dependent upon what foo is. If you use an example that people will potentially find plausible, it may mask the error in reasoning (in the same way a faulty syllogism might seem like good logic because it results in a conclusion you like). Again, if you use a more extreme example, however, the logical problems become (hopefully) clear.
Rational thinking, and logic, are rational (and logical) regardless of what the objects discussed are. If changing the objects discussed makes it obvious that the thinking isn't rational (or logical), it wasn't rational (or logical) before the objects were changed.
As you should well know, if you are employed in the sciences.
RC