My hypothesis is that in most cases the burners may not have been manufactured by the lantern manufacturers. I think that in many cases they were made by others and marked for the individual companies like "jobber" lanterns, especially in the case of solid brass burners. Some manufacturers like Plume and Atwood and The E. Miller Co. had complete lines of burners for every lantern and lamp known to be produced and some custom designs. Many times I have found burners from both of these companies in various lanterns made by several companies. I have often thought these were offered as upgrades to the originals since brass burners were touted as more efficient and less prone to corrosion than the standard tin plated ones. As far as the switch to 7/8" wicks from 1" in the No.2 burners goes, I could not say when, it bears further research. If the catalog says it is fitted with 1" wick I use 1", if it says 7/8" wick, I'll use 7/8". If the 7/8" wick is too loose and doesn't burn properly, i.e. a flickering or unstable flame, I'll stuff a 1" wick in it which usually cures that kind of problem. And finally, interchangeability of burner sizes and some specifications (candle power rated output etc.) regardless of whether they were true or not, allowed the competition to acquire a larger market share of sales in a given sales district.