Any kind of lead screw arrangement is going to wear, so the click indexing method is, at least theoretically, a flawed design. Minor variances in the position of the cocking piece sight would, also, theoretically, add to the dispersion of shooting. Whether the movement of the cocking piece sight would make the shooting less accurate, in the practical sense, than the backlash in the Lyman 48 adjustments, or in a well-used Whelen bolt-shroud adjustment screw, or the eye error with the notch-and-bead barrel sight, or the slop in standard "set and forget" hunting scopes, is the real issue.
The only people who really are affected by these considerations are the most critical of target shooters, those guys who shoot at game animals at extreme distances and write it up to impress the natives, and gun writers pressed for a topic and a deadline. The problem is that their complaints get to the ninety-and-nine who would otherwise be using these sights with perfect satisfaction. Hope springs eternal that some minor technical improvement in equipment will take them from the chimney-corner of their "B" shooting to the cotillion of "AAA" shooting with no additional effort on their part. They abandon the good old standbys, which then go out of production, and spend more money on the latest advancements. Their shooting does not improve much, and the marketers are pleased with the new revenue streams, but the ultimate result for the rest of us is the reduction of the choices in equipment we used to take for granted.