Joe's original work specified a MTM, with specified distances apart, and specified crossovers.An array that looks like this
o
o
o
o.
o.
o.
o.
o. 0
o. 0
o 0
o 0
o 0 BIG O(sub woofer)
Where the odots are tweeters, the small o' are mids, and the right O's are woofs, isn't an MTM. And the 0's are in a separate ARRAY altogether
So I'm not sure what you mean when you invoke Joe's MTM
Can you clarify?