None of what was planted last fall seems to have winter killed, my plots look pretty awesome right now. Crimson clover, alfalfa, winter wheat? ,there are some turnips it seems, rape, and I think some radishes left in there. My plots have never looked this good!
Does it make sense to mow it now ?
If you have good deer browse you may not need to mox. I almost never mow my clover unless it is for weed/grass termination. Remember, larger clover/more leaves improve nitrogen scavenging. This will be banked for your next round of planting.