I agree. Actual, as a Baptist, there are several minor things with Luther and Calvin I would disagree with. I think these were carry overs from their Catholic days (like the perpetual virginity of Mary). Whether they actually believed it, I'm not sure but I don't think it was high on the priority list and, given the times and men, I don't think they wished to discuss it.
So, your contention is that Luther and Calvin gave sermons on things they didn't actually believe? What other things did they speak about that they didn't actually believe? Isn't preaching a sermon on a topic a priority? I would think that if it was such a low priority, they would have remained silent on the matter. What about Wesley? He was preaching more than two centuries after Luther and Calvin?
Then again, if this is a "minor" thing that you disagree with the Reformers on, then why is it such a major issue to you today?