What is the wording on Heartseeker Strike?

So I was looking through Pantheons abilities to make a review for him because I thought it would be fun and I noticed this odd bit of wording on his E:

Active: Pantheon focuses and deals 3 swift strikes in front of him for 13/23/33/43/53 (+60% bonus Attack Damage) physical damage per strike. Deals double damage to champions.

I find this weird because most of the time, it now gives the total damage against champions and says the damage is halved against minions and monsters, not the other way around. I'm guessing it's because he's an old champions but what confuses me more is if that's the case, why hasn't it been changed. I seems like a minor thing but it's really weird