I think Cephallus's point is not to say that we shouldn't try to get people to see us, just that at some point you DO have to draw a line between safety and insanity.
I can see a third brake light, that is pretty standard on many cars like ours, but at some point, you have to say this is good and not keep adding lights (
).
Personally, when I get the opporitunity, I will probably install a third LED light at the top of the rearview window and say it's good. It doesn't have to be blindingly bright, just visible.