The frustrating mistake in Gil Student's post about shul singing, as aptly noted by a reader named Simon, is this: "authentic" and "older" are not synonyms. In Gil's imagination the custom embraced by the Brooklyn men with the longer coats and beards - in this case responsive shul singing - is better and more authoritative.
But this is absurd.
There is no reason to presume the responsive custom Gil prefers was ever universal, nor do we have any evidence that the custom was established deliberately with any higher purpose in mind. Singing responsively is just what some people did, at some point in time. Elsewhere, it was otherwise. In fact, we can't even prove that the responsive style was the first custom: Perhaps the Eastern European Jews Gil venerates broke with a previous tradition. Perhaps the very first time Jews gathered to sing Kel Adon they did it congregationally. Who can know? The answer is lost in the mists of time. This much, however, is certain: The idea that everything Jewish was forever immutable and inalterable until c. 1939 is the sort of sloppy thinking that causes grown men to use phrases like "Torah-True" or to presume that Moshe wore a shtreimal.
Honorable mention: Lipman tears into Gil.