Have a look around chaps during the day. Now tell me what you see first. The nav lights or the Aircraft???
Many Airlines around the world don't use Nav lights for day light ops. Whats the point?
Now check the ANO and see when Nav lights should be used. I cant find anything about them being used during the day.
I tell you what, lets put are lights on every time we drive are cars!
If its SOP use them. But if it isn't DON'T.