what i mean is -how- does an mtm or tmm do what it does? is the m&m like an array of 2? how do you figure out where to put the 1st "m", 2nd "m" and "t"? also what happens at the crossover from "m" to "t"? sorry for so many questions. i am trying to understand how this works and wanted to be more specific with my questions than just "how does that work". tia, zonkers