First, great thread, and no raw nerves here.
Second, I understand your point. But to state the obvious, these reviews are inherently subjective. And I think that what you've noticed is that -- at least in non-blind reviews -- people tend to rate cigars by how well they match their expectations. From those to whom much is given, much is expected. If I pull out a house brand alternative and it's well constructed, burns well, and shows more complexity than I'd expect from a house brand, and, indeed, as much complexity as one of the better premiums I've smoked, I'd be inclined to give it 4-5 stars, because it was much better than expected. If, on the other hand, I smoked an uber-premium and it has any flaws in construction or has something less than sublime flavor and transcendental complexity, I'm inclined not to give it a 5, and maybe only a 4, because it didn't meet my expectations. Now, if I smoked the first, surprisingly good bundled cigar and the slightly disappointing uber-premium blind, in a head-to-head smoke off, I might rate the uber-premium more highly, and perhaps much more highly (but, since it's a blind tasting, maybe not . . .).
Thus, two cigars with the same rating -- even from the same reviewer -- can't be considered equal, simply by virtue of the equal rating. I don' t mean to pick on anyone by name, but just to take up your example, I wonder if Scott (Texlewee) would tell you that he'd rather smoke the Vegas de Fonsecas that he just gave 5 stars and not the Opus X Reserva de Chateau that he gave 4.5 stars. Maybe he would.
That's why the narrative description is so much more important to me than the rating. I try to explain why rated it where I did, and what standard I measured it against. Sometimes I'll say that this was a surprisingly good cigar for its price point, and therefore I've bumped it up half a star. Sometimes I'll say that a super-premium cigar was a bit disappointing, and therefore I've bumped it down a half star.
I guess my point here is that we can't demand mathematical precision from these ratings, nor expect that every 4.5 star cigar is equally good. What we can ask is that reviewers give enough information and explanation for us all to be able to understand why they liked or didn't like a cigar, and, in particular, whether they are tougher when they grade a super-premium as compated to a budget smoke. I'll admit that I can't help but demand more from super-premiums.
Again, great, provocative post.