Well, with respect to #18 (or a portion of it), I can tell them where the "s" in vs. went. It was a casualty of modern "legal style" thanks to the court system.
The various state and federal courts, as a group, set the appropriate citation styles for legal writing. And, somewhere in there, someone decided to drop that "s." I have no idea what it did to piss them off .... but the correct citation style has (for many years now) been "Plaintiff v. Defendant."
And, I would guess that this has now leaked over into common usage.
Hey ... these things happen.
