Air chamber--drop elbow vs drop tee?
Why does it seem customary to install an air chamber as a water hammer arrestor using a brass drop elbow with a tee fitting beneath it to branch off to a separate arm, like a saquaro cactus? Wouldn't it be easier just to use a brass drop tee and extend the piping up to form the air chamber? When the stub out the wall is just a copper pipe, it seems common to do this with just a sweat fitted tee.
I'm aware of the debate as to whether air chambers are useless, anyhow, but I intend to install one for the feed to a new toilet, just in case. I want to make sure I'm not overlooking something on how this should be done.