The use of masks does affect the mesocontrast in ways that film and film developers do not address. Additionally the use of masks addresses the other end of the paper scale from that accomplished through flashing the paper. My experience has indicated that paper and paper developers do not address the mesocontrast as effectively as does masking in my experience.
I would be interested in your experience with masking should you desire to try it. Thanks again for your well thought out and written response
Don, I figure I make this my last post here, and perhaps leave you with one more trick.
Something I found useful before doing more involved techniques was going to a higher paper grade and then use diveded developing. This seemed to "clean" the middle tones and at the same time mantain the overall contrast. Funnily enough to do this with alt printing you have to increase contrast and increase exposure time....go figure....