Agree that the river is a strike and should be called a strike.
I seriously think that someone in this area is giving umpires a rules update that is similar to Bretmans analysis and they are misunderstanding it. The experienced umps understand it, some don't.
Will add that I have no doubt that how a catcher sets up can affect whether a pitch is called a ball or a strike. Not really framing but staying in a position that helps ump see or not see certain pitches. I have seen this first hand many times, fans think pitch in same location is ball for one team and strike for other team. They are right but it isn't favoritism. The difference is almost always the catcher. I wish I knew more about that, it seems like there is low hanging fruit there for most teams.
I want to make something clear- I rarely get on umps and never let kids blame umps for a kids success or failure. As bad as calls can be, you can't let a kid think their fate lies in the hands of others, they have to get it done.