A little background; being only 33 yrs old, polypro baselayers is a little before my time popularity wise. I didn't even really know about them until somewhat recently. At first i didn't consider them because of the horrid smell factor, but i got to thinking about other possible uses besides using them as a baselayer.
I've wondered about using it for midlayers, specifically in the context of cold and wet conditions. For an example, i was thinking of trying this--wearing a thin merino or merino poly/or acrylic blend for a baselayer, wearing a thinnish polypro "baselayer", which i've soaked in DWR, over the top, and then wearing say my Brooks LSD II windshirt as the last, outer layer in cold rainy conditions. I would probably attach a polypro hood to the polypro mid layer.
Has anyone tried this, or something similar to same for these kind of conditions? Polypro seems to have so many advantages for lightweight backpacking that it seems a shame to not use it. It's very light weight, extremely hydrophobic, very thermally non conductive, and while not as durable as nylon or even polyester it's still more durable than most natural fabrics--especially more than thinner merino wool.
Wearing the merino underneath should minimize the odor factor, by filtering some of the body oils, dead skin, etc.
Thoughts, experiences, opinions?