For those of you who just looked at the picture without reading any of the thread, you seem to misunderstand one thing about the outline: it is *never* on unless you tell it to. Everything is exactly the same as it is normally until you press a hotkey (eg: tab), in which case the outlining is enabled until you press that hotkey again. It's not meant to be played with it on, that'd be ugly. It's simply meant for players who cannot distinguish if a unit is theirs (ie: on a mod that doesn't have or lacks good teamcolor), in which case, they can hit the hotkey, see it, then hit it again.
What difference does it make to you? Well, if you don't like it, you will never see it, unless you accidentally hit the button in game. It would *always* default to off, and wouldn't have an INI setting for it either, since it's a per-situation feature. I myself wouldn't use it much, as I am perfectly happy with how team color works, but if you have a group of units in a forest and can't see them, or there's a massive battle going on with 3 or 4 different teams, then that might be (very) helpful.