Beware of the Train

I guess it depends on what you mean by "comparing" - it has two senses, one being to suggest that something is like another thing, and the other being to examine two things in search of both commonalities and differences. I think the question about cranks (ie, people whose views we can reasonably dismiss without fully examining every part of their argument) is conceptually important even if we are not really talking about cranks, or we are talking about "camps" that contain both cranks and non-cranks. Because it's about establishing the boundaries of rational discourse; in some senses, a commitment to truth requires of us that we treat as infinite our own capacity to listen attentively to ideas with which we disagree, to patiently consider viewpoints we are unfamiliar with, to examine and re-examine the basis of our present understanding and that of others and to search for ways to correct and improve both, &c. And yet, in reality these capacities are not infinite, and by failing to dismiss some ideas we may diminish our capacity to address ideas which genuinely deserve deeper consideration. And yet, of course, the tendency as soon as we have allowed the possibility of dismissing some ideas out of hand is to use this as a tool to let ourselves off the hook for thinking seriously at all, since whichever ideas most deeply threaten a framework in which we are ego-invested are likely to be the first we label as crank-ideas. Anyway, I think it is genuinely a Hard Problem and not just an easy excuse to avoid uncomfortable questions.