Keep in mind that these are of course optimizations. What should happen in the perfect party.

What you get in DF will not always conform, and if you have a tank buddy who doesn't want to perform the prescribed role, whether it be because of inexperience / lack of confidence (this is okay) or laziness / stubbornness (this is not, but it will happen anyway), the relevant question will sometimes be not "which job should MT?" but "which position is more difficult/technical for this particular fight?"