It would also make for one heck of a circus ring of cables around the room.
I'm not sure my large dog would appreciate the barrier to her favorite floor spot in front of the M60s.
You are right though. That many subs would likely create havoc with cancelling (or amplified) LFE sound waves all over the place. I doubt it would sound particularly pleasing or effective, but if the individual LFE signals and subwoofer gains were set right, it could work.
Another experiment to add to the growing list.

"Those who preach the myths of audio are ignorant of truth."