Ave Maria!
Mary’s role as Coredemptrix is Scriptural and rooted in Tradition—Saints, Popes, theologians and faithful alike have always seen Our Lady’s role in our salvation (always secondary and subordinated to Christ) as important.
Check out this link
http://www.voxpopuli.org/response_to_7_common_objections_part1.php
Also, Monsignor Calkins has some excellent articles on the web on this topic, such as
http://motherofallpeoples.com/index.php?option=com_content&task=view&id=833&Itemid=40
God included Mary in His plan for our salvation, including her sorrows with and under Christ for the sake of His Church during the actual event of our Redemption on Calvary. A dogma on Mary’s spiritual motherhood as Mediatrix of Grace and Coredemptrix would clarify that she is not equal to Christ in her role, yet would uphold her unique participation in the work of our salvation and her unique role in dispensing God’s grace to her children.
Peace...
Just wanted to add that I agree with you Andrew to the point that God does not need us. That would be silly to say that he needs us for anything. But He does apparently want us or He never would have created us. And if He wanted us enough to create us then who are we to say that He does not want us to participate in His Salvific actions. Even the Protestants who are so big on God-alone seem to go through great efforts in passing out bibles and preaching from it. Does God need Bibles or preachers? Certainly not. He did not use any for Paul on the road to Damascus. If you follow this logic to the final conclusion then we should do absolutely nothing. But if you say we should do something (as you seem to be saying by continuing to write in this blog) then you must agree that it is a matter of drawing the line somewhere as to what things we should do and what things God should do.
Fr. Maximilian points out that according to the Bible, God DOES want us to participate in His salvific plan. If you say God does not want us to participate then the burden of proof as to why we should redraw these lines is now on you.
Ave Maria!