To say that ‘redemptrix’ has nothing to do with ‘redeem’ is as absurd as saying that ‘dominatrix’ has nothing to do with ‘domination.’
You wrote:
“To say that redemptrix has nothing to do with redeem is as absurd as saying that dominatrix has nothing to do with domination.”
You are making a logic error. Yes, redemptrix has something to do with redemption. But it has NOTHING to do with the singular redemptive act of Christ on the Cross in any way that detracts from Christ’s sacrifice. I pointed this out and posted a link to a source that ably explained this. Why are you still making the same error?
As Martin Beckman explains:
“Jesus Christ as true God and true man redeems the human family, while Mary as Coredemptrix participates with the Redeemer in his one perfect Sacrifice in a completely subordinate and dependent way. The key word here is “participation” in that which is exclusively true of Jesus Christ. The title “Coredemptrix” never puts Mary on a level of equality with our Lord; rather, it refers to Mary’s unique and intimate participation with her divine Son in the work of redemption. “Coredemptrix” is a Latin word; the prefix “co” in the title, “Coredemptrix,” derives from the Latin word “cum,” which means “with,” not “equal to.” Mary’s sufferings are efficacious towards the redemption of man because they are wholly rooted in the redemptive graces of Christ and are perfectly united to His redeeming will. Similarly, as Mediatrix, the Mother of Jesus does not “rival” Christ’s mediation but rather participates in the one mediation of Jesus Christ. Imagine water from a reservoir reaching the people through a system of aqueducts or channels. By analogy, Jesus is the infinite “reservoir” of all grace, which is distributed to us through Mary .... as she gave birth to Jesus. Jesus, the one mediator, does not exclude secondary, subordinate mediators.”
http://www.catholicsource.net/articles/coredemptrix.html