ive been reading this thread up and down, and i must admit, i dont understand the point the OP is trying to make, maybe i missed a post that would clear it up.
how is it the responsibility of non-believers to disprove the claims that believers had made? its a matter of evidence to support one's claim. disbelief in a claim that has no supporting evidence is not only rational, but its the only rational position one can take.
for the example of the black swan. it wasnt unreasonable to disbelieve that a black swan existed when there was no evidence presented that it did indeed exist. to not believe in black swans once evidence was presented would unreasonable.
of course, belief and knowledge are 2 different things, and there is no need to believe in something that you know exists. black swans exist, we know that, theres no need to believe it. we know they exist because of evidence. so how is it unreasonable to not believe in black swans when no evidence of them had ever been presented?
i would agree that personal experience is evidence for the person. but you cant expect others to take it as such. and of course, personal experience cant be disproved, because personal experiences exist. but the same experience can be perceived differently by different people. and plenty of personal perceptions of experience have been proven to have been perceived incorrectly. examples being cases of ufo sightings, alien abductions, & big-foot sightings.
ufo's, alien abductions, & big-foot may well exist, but personal experience cant be counted on as hard evidence. we may both see the same animal, you may think its big-foot, and i may think its a bear. our perceptions of the experience has no impact on what the animal actually was, it could be either or neither. but the belief that the animal was a bear would be more reasonable since bears are known to exist, and big-foots are not.