Back in the day, a guy brought his grandfather's K frame into the shop. Unworn tan box with blue lettering, bluing you could fall into, glorious color case hardening. After I rhapsodized about how they don't build them like they used to, I asked why it had been brought in.
"Spits lead".
Puzzled, as it showed nearly no wear, I swung the cylinder out and bust out laughing. There was no forcing cone in the barrel tenon.
The point I'm trying to make is that the way we think things were made back in "the good old days" isn't necessarily so. Otherwise you wouldn't have had armorers being taught how to optimize/blueprint the final product. And, that was, SFAIK, only for the law enforcement market. Or, maybe for special customers.
The other thing is that for most of the folks who bought firearms back then, and now, the firearm is just a tool. And, that tool has to function under any/all conditions, not just during a bullseye match. That takes/took precedence over the preferences of a comparative few. I expect that's still true when you're looking at keeping the company in business.
I do understand your preference, but as someone who spent decades using what's issued, as issued, it's surprising what you can do with what the factories make. Maybe with just a smidgen of armorers adjustments and a lot of practice.
Your particular point, mainspring tension: the factory minimums for a stock K frame .38 Spl is 52 oz, for .357 is 56 oz. I've measured many a K frame from the factory at or above 64 oz., but that was sometime back. OTOH, a tuned .38 can go much lower, but that's for playing games.
