@millercarbon --
If that's what Duke truly means I don't see how his recommendation to connect my subs in stereo (in proposed diagonal setting) would be of any consequence. That is, his recommendation wouldn't be wrong as such, but why opt for stereo if it's rooted in the conviction of being moot to begin with?
Even so, arguing in absolutes on stereo vs. mono bass doesn't come from you preemptively knowing about this field to the bottom of the matter, but rather your wanting to be right about it; pragmatically I'm sure you speak for many, but what you're doing with it is just being overly reductive.
When Duke says "My understanding is that true stereo below 80 Hz is actually quite rare" what he means is unicorn rare. Something people talk about but never quite manage to find. There is no stereo bass information down low. Even if there were we’d never hear it.
If that's what Duke truly means I don't see how his recommendation to connect my subs in stereo (in proposed diagonal setting) would be of any consequence. That is, his recommendation wouldn't be wrong as such, but why opt for stereo if it's rooted in the conviction of being moot to begin with?
Even so, arguing in absolutes on stereo vs. mono bass doesn't come from you preemptively knowing about this field to the bottom of the matter, but rather your wanting to be right about it; pragmatically I'm sure you speak for many, but what you're doing with it is just being overly reductive.