Minimum Necessary Force
A certain variance *on either side* of the right amount of force is reasonable -- only people who use significantly more than the right amount should be prosecuted. Also, the right amount to aim for is more than the "necessary" amount, strictly speaking, because we shouldn't have to take undue risks. The minimum necessary force concept pulls against both these points, and is thus highly misleading.
can you give a concrete example illustrating the MNF concept?
i'm imagining an intruder breaking into my house. he has a mask and i see a gun. so i shoot him. [fill in the rest]
MNF is not precisely defined.