Curious record side labeling


Do any of the jazz gurus on here know why some double-set records have this curious side labeling where record 1 has sides A and D, and record 2 sides B and C? It does not make much sense to me, and I wonder what purpose it serves other than to confuse the listener. I noticed this with a couple of Coltrane records from the '60s, recently with "The Other Village Vanguard Tapes."
actusreus
When I first got into the audio business, one of my stores sold a really nice Technics changer. It was actually a pretty decent table. We also sold the BIC and Dual.
Good info guys. Changers seem the antithesis of the audiophile analog...Stacking bare records, dropping one on top of another, automatic restart, 6 gram tracking carts...Brrr :)
I may be the oldest f*rt to post on this thread (born in 1947), and of course I remember record changers. I did own a Dual 1015 in the late 60's, but never stacked records on it. Rightly or not, I was concerned that it might damage my records: I reasoned that no good could come of dropping a non-spinning LP on top of another moving (at 33 1/3 rpm) LP.