I guess I should elaborate
The room is a custom design (golden ratio)
Floated floor, bass traps
Tons of absorption & diffusion on the walls & ceiling
All Martin Logan speakers & subs so well integrated
And the Trinnov preamp/processor to tune all the channels to match room response for amplitude, phase & delay
But since I've gone that far, I'm just trying to take any last possibilities into play. Companies that record for surround like 2L & Sono Luminus and definitely Steven Wilson purposely put a full range of sound into each speaker on the left side & right side of the array.
My question is more, will I lose some of the utility of the 1/4 placement for wave cancellation if both left and right front subs aren't playing the exact same signal i.e. left sub has left side low pass info and right sub has right side. If they both have the summed to mono total of all speakers then they will be playing the exact same signal, hence the bonus of cancelling axial modes. If they don't then I may lose that help in taming the room for a potential bonus of a moderately perceptible (if at all) ability to recreate the effect of using all full range speakers and the same imaging as the recording engineer's mix or better, the ambience of the room where a live recording was made.