I would like to use a real-life, so I will go with the cliche of Klingons being a cross between Japanese and Norse.
And in Japan it did work that way, after-all the samurai did depend on the craftsmen and sword-smiths and still consider themselves to be on a higher social level.
Both the japanese and the vikings WERE
scientifically/technologically and economically stagnant. And, for the vast majority of the population, life in these societies was brutish and short.
That's what you get when your craftsmen, sword-smiths, etc - pretty much 99% of your citizens - are second-class citizens, living in poverty.
Tell me - do you know what was the punishment for a samurai killing a peasant/craftsman/sword-smith, just because he felt like it/got a kick out of it?
That's what you get, generally, when you have an oligarchy whose main jobs are to squeeze the rest of society for all the wealth and to secure its future prominence (waging wars, largely for 'macho' reasons, in the process). For proof, look at most human societies that existed.
That's an accurate description of the klingon society - as shown on screen. That the klingon empire kept up with the federation, for centuries, in terms of wealth and technology, is a poetic license - you just have to suspend disbelief and accept it; in actuality, it's just as realistic as the transporter.
I may be going in circles here, but

.
Christopher's analysis is correct. You're trying to refute it with arguments he already proved unconvincing. Of course, that doesn't stop you from repeating them.
So - yes, you are going in circles.