Not only does he forget his grandsons name, when you deliver his parcel later he's like "It's great to see you player, you're already doing so well!" and then his grandson arrives and Oak is just like "Oh, yeah. Hi Blue. You're here too, I guess."
I remember after you beat the Pokemon League he's like "Grandson I'm disappointed. You clearly lost because your Pokemon hate you."
Like damn, Oak, that's cold. You're going to give that kid a complex.
Justice for Blue/Green/Gary/Fartass or whatever his name is supposed to be.
I think it's funny that you can tell him whatever name you pull out of your ass and Oak will believe you and call him that for the rest of his life.
Poopyface