KingofIce

I don't think that it has anything to do with what he was known for as you put it, then again you seem to really like Robert Baratheon. It has more to do with the fact that it proves that Jon was not Ned's bastard and Ned was not dishonorable in that respect. That Jon is part Targ making him have a claim to the throne by blood. Along with adding more to the idea of Jon being Azor Ahai or Prince that was Promised.