challengers twitter pointed out something very cool: art's coach speaking to him in german!
the subs says "just invite her to serve." (which doesn't make any sense? and art doesn't even go to her after that lmao?) but he apparently actually says "wirf den ball etwas höher." which means "throw the ball a little higher.".
so art knows what patrick's house looks like which means he went there, he understands when his coach speaks to him in german and he's the only one who can pronounce "zweig", a german surname, the right way.
art learning german for patrick and spending holidays with him and his family is canon, i don't make the rules.
“jensen wouldn't be able to differentiate between me and cas” misha my dude jensen is not even able to differentiate between dean winchester and himself so