Actually, if you'll watch carefully, here is the actual pathological process:
They are unable to jettison the mental residue from pondering Possibility 1 before they turn their minds to Possibility 2. That means the possiblities have a CUMULATIVE EFFECT in their minds, so that a subjective PROBABILITY THRESHOLD is soon reached, and they interpret a dozen possibles (improbabilities) as a cumulative probability.
They can't seem to grasp that most observations are independent of each other, i.e. one possibility doesn't make the second possiblity any more likely.
Zero times 12 equals zero, not 12.
It is a fascinating process to watch in a sort perverse way. The most common rationale/equation is the number of times an assertion is made is a clear indication of the validity of the assertion. A corollary equation is the volume in which the assertion is made is further evidence of its validity. Another is the notion of the sum total of irrelevancies you can pile on to the assertion augments the assertion.
Oddly...Jamaksin uses the same excreable tactics that OJ Simpson's lawyers used bamboozle the jury.
I particulalry like your observation that nutballs transmute the sum of possibilites into probabiity. Candidly, I don't think jamaksin would find any fault in that logic.