While David wrote the above, I think he left out a word. "I could see no SCRIPTURAL basis for a belief....etc." in the second sentence of the above excerpt. It makes all the difference.
Assumption, Immaculate Conception, Coredemptrix, and Mediatrix: with the possible exception of "The Assumption", all the above four are without scriptural foundation that I have ever read.
Scott Hahn, in one of his books I've read, suggests the Assumption is depicted in Revelation 12. I don't think it's a close call, but there is a bit of a point there.
I'm open to hearing scripture that does provide a foundation for those beliefs.
Let's just see...