What the Reformers believed about Our Lord's Blessed Mother would never lead to veneration though, would it? Since you're quoting Luther and Calvin. Luther said that he didn't think saying the Hail Mary would be much of a problem for someone whose understanding of the Faith was solid, but that it wasn't something that should be encouraged.
Departing from that point, back in April of this year, National Review carried a review of some book by Fr. Nehaus. He stated that one of his parishoners told him that she didn't bother going to Christ because she had His Mother instead. He wrote it off as unimportant and just a case of 'bad theology.' But I think it's much more than that.
Back on the L&E thread you noted that it was considered sinful to pray to Christ for the little things, that that's what the saints were for. I even think you said that your assertion was to be found in Scripture. I saved the post but don't have it at the ready right now. Can post it later, if you'd like. Not trying to play gotcha here, just want to point out something you said that I thought was wrong, and allow you to elaborate if I misunderstood or misinterpreted.
I was once driving somewhere and praying a Rosary. I got lost. The mystery I was meditating on happened to be Mary finding Jesus in the temple. The concern about finding my way in the streets combined with the picture of Mary looking for her Child in the pilgrims' traffic. The beads became a hand guiding mine. After the decade got said, I realized the state of my mind and was amused by the blend of the everyday and the eternal that my prayer contained. It was not an intercessory prayer, -- I was not praying to find my way, and I was not particularly distressed by being lost. My greater concern was not to lose concentration on the Mystery while making turns and traffic stops. I believe this episode shows the power of a meditative prayer that matches the everyday worry: it made my meditation on the Gospel extremely vivid.