[TheStickman]

Never heard a word about the Blessed Mother being *co-redemptrix*.

I have heard and read about the Blessed Mother being *co-mediatrix*. I concur with you on *co must mean equal* nonsense. Words mean things no matter how hard we might wish them to mean something else.

[Bainbridge]

Well, go ahead and goggle it.
You will find plenty of reading material.
Try, for example, Catholicsource.net.
They are perfectly comfortable with the title.
You are most right on one point however: Words Do mean things!