The self-fulfilling prophecy in this case being that fuse directionality and wire directionality are not real, that they're FALSE. In this case the self-fulfilling prophecy is being perpetrated by the, uh, Three Amigos. So what is a self-fulfilling prophecy? A self-fulfilling prophecy is a prediction that directly or indirectly causes itself to become true, by the very terms of the prophecy itself, due to positive feedback between belief and behavior. In the case of fuse directionality the self-fulfilling prophecy takes the form of, "fuse directionality disobeys the laws of science and electricity so must be patently FALSE." And it can be "proved" scientifically and mathematically that fuse directionality is FALSE, a myth.
The self-fulfilling prophecy is, in the beginning, a FALSE definition of the situation evoking a new behavior which makes the original false conception come true. This specious validity of the self-fulfilling prophecy perpetuates a reign of error. For the prophet will cite the actual course of events as proof that he was right from the very beginning.
In other words, a positive or negative prophecy, strongly held belief, or delusion—declared as truth when it is actually false—may sufficiently influence people so that their reactions ultimately fulfill the once-false prophecy.
See also Backfire Effect, which is very similar to Self-Fulfilling Prophecy. This thread also provides abundant examples of the Backfire Effect, embracing false beliefs even more strongly when confronted with contradictory views or evidence.
cheerios