Fleib, I am not sure I follow your argument to the point where I can agree that using a "modern" mono cartridge is inherently superior to using a mono switch on the linestage, to reproduce mono LP sound. But further, I was remiss in not clarifying that the mono LPs I had in mind would be very late in the mono era and/or modern re-issues of pressings that were originally mono. There are long discussions on various threads about how these are created, but I was assuming they are typically consonant with playback by modern cartridges (because they demonstrably are). I was not trying to take into account early mono LPs where indeed the groove width was different, etc. That adds a layer of complexity that kills the discussion. Further, the paragraph you quote is not one that I wrote, I don't think. Also, I never argued that using a mono cartridge is a bad idea.
Johnny, No, I don't know for a fact that "most modern mono cartridges" are internally stereo cartridges in which the two channels are bridged at the outputs. But for sure, many are built that way, if not most, based on testimony of persons who would seem to have inside info. And finally, the fact that your mono cartridge is dead quiet is in no way a refutation of anything I wrote. To wit, a mono LP has no music encoded via vertical modulation. Thus, the only "signal" generated by vertical deflection of the stylus in a stereo cartridge that has been converted to put out a mono signal, when playing a mono LP, would be noise. Typically such noise is identical in both channels and would be cancelled when the two channels are combined to produce mono. (I wrote this above.)
Johnny, No, I don't know for a fact that "most modern mono cartridges" are internally stereo cartridges in which the two channels are bridged at the outputs. But for sure, many are built that way, if not most, based on testimony of persons who would seem to have inside info. And finally, the fact that your mono cartridge is dead quiet is in no way a refutation of anything I wrote. To wit, a mono LP has no music encoded via vertical modulation. Thus, the only "signal" generated by vertical deflection of the stylus in a stereo cartridge that has been converted to put out a mono signal, when playing a mono LP, would be noise. Typically such noise is identical in both channels and would be cancelled when the two channels are combined to produce mono. (I wrote this above.)