He says it in one of those posts--companies did redubs to simply bill more. It was standard practice back then. It was also sadly standard practice in the 70s for a lot of actual masters to just get thrown out or they were poorly taken care of. ABC in particular had lots of cost-cutting which resulted in lots of sad consequences. Michael Cuscuna who has overseen tons of jazz reissues said this:
"When I first went into the Impulse vaults in 1978, they had been very mistreated. The tapes had been moved from New York to L.A., so as early as 1969 or '70 there was already stuff missing. I was able to find a lot of good Coltrane that was unissued, and of course I tore the place apart trying to find what I thought was an entire alternate version of [the]Love Supreme suite, with Archie Shepp and Art Davis, but found nothing..."
"I'm ninety-nine percent sure the master tapes of A LOVE SUPREME were scrapped. This happened to a lot of popular recordings in the seventies, not only jazz. They would dub from the original tape, making new masters for fear that the old one was wearing out, oxide was falling off, or the splices were getting old and drying up. That's OK, but often they threw the original away because they didn't want to double the tape inventory they had!"
And from Ashley Kahn's book (the foremost expert on Coltrane) regarding ALS:
all previous versions were from a second generation master. A first generation master was found at EMI/Abbey Road studios where it was shipped for production of the LP when it was first released in 1965. The book also says that, unlike previous versions, this new tape was not compressed or EQ'd. One more reason to buy this classic again.