200R4 vs A518 vs Keisler A41 fitment

Just asking, not trying to be an ahole,
but
but, you have 440 in a lightweight Dart that already runs at well well under
8-pounds per cubic inch, even with a heavy driver;
so why, jus asking, are you entertaining an overdrive? versus
just a smaller rear gear and/or, a lil more stall?
I get that there are reasons; just trying to understand.
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Just to compare,
I run, a street 68 Barracuda fb, at 10 pounds per cube with my SBM,
and altho I do have a GV-od (with an A833), I bought it for split-shifting, to keep the little engine on the small cam, and to one-time, cut a sharp Eighth-mile using four gears . Low-rpm Cruising, for me, was just a side-benefit.
But if I'd have had a 440, Ida never bought that overdrive. Course I wouldn't have had the 4-speed either, lol, and probably not that pig-heavy A-body either, more lols. Ima thinking a New Yorker, yeah ....................
Like said, just trying to understand.