James Randi begins on the premise that he is a skeptic. . .but he has always assumed the impossibilities of 'the psychc'; and his investigations are no more than a personal testimony to his determination to confirm his belief in the Randi Psychic is Bunk theory.
His investigations; while they bear honest asssesments; are nonetheless, in many cases a 'truth stretched or shaped' to meet his core belief. His investigations bring one no more to a higher 'truth of the matter' than do those investigations done by a 'true believer' who begins - and ends - with a confirmation of psychic reality.
What IS necessary is an unbiased and open - but discerning - mind when approaching 'psychic/paranormal' research (as is required for any honest, credible inquiry/research, for that matter,of course). All to say, that James Randi as a disbeliever gets one no further to the 'truth of the matter' than the researcher who is already convinced that all psychic phenomena is genuine; and is determined to prove just that.
Meantime, there ARE numerous books that discuss well-researched/well documented laboratory experiments where 'statistical probabilities' are challenged by their results.
We cannot discount the role of 'observer' here as well (as per quantum physics/Heisenberg Principle etc. . .) which in itself. . .leads one to what might be described as seemingly 'paranormal' - if not mystical - considerations; if not translated as unreal. . .or just 'erroneous'.
People believe what they want to believe regardless of the facts. Much like Libs.