Solved! Go to Solution.
Solved! by mathewk. See the answer in context.
I've used Matt's solution. Select All, Remove the MText (it helps to have selected the MText first so you can grab it as a Previous selection) then move to back.
Sometimes you have to do a regen in order to see the text being masked.
While draworder seems to be much more reliable than it used to be, I wish Autodesk would implement draworder by layer, which is something I think Microstation does?