I saw that in the last journal of 2007 the article about M. mieheana, which seemed to suggest that it wasn't the species described by Tiegel, but a form of densispina, changed as a result of lighting conditions where it grew to the form of plant as we know it today.
I've always thought it was a natural hybrid between elongata and densispina, so it will be interesting to see the plant that the Schmid's have discovered. Is the matter only in the loose leaf collection? or in the journal (which I shall now await eagerly!).