Ok, if that is truly what it means
then what is the point in having that in the game?
DMI: The overall player index, DMI, gives a very rough indication of how good your player is. This is a good way to check that your player is getting training, but is otherwise a lot less meaningful than it first appears. Be warned!
I guess I should just start treating it like it should: meaningless
That would be really tough with the various skills that go into DMI.