Leg Kick?

One of the kids on my team has a leg kick kind of like Bronson Arroyo, but less extreme. Does this hinder his velocity or anything? Should he get rid of it or is it fine to keep? Thanks

sandy koufax used to have a point in his delivery where his leg was striaght just like bob gibson or warren spahn or pretty much everybody who pitched in the70s and under. to close the knee at his apex is just a new tendencie. let him keep it like he’s comfortable it doesn’t change anything. plus he’sd making the batter go wtf? for a second which gives him an edge.

alright great, ill let him know.