A little lecture on aftermarket axle rear covers

Yeah, that visual test is a joke. How did that clear cover replicate the original one they machined? It sure doesn't look similar in shape to me. Why didn't they take it one step further and make a clear version of theirs to prove how well it redirects the oil rather than just talk about it? And is a 15* temp different that big of a deal??? Marketing hype if you ask me, though admittedly I don't own a tow rig.