Was at the Overland Expo N. C. last weekend and it was MUD, MUD, MUD everywhere! Wifie, who was sitting in the front passenger seat with window open, even got a little bolus in her face!
The wrangler was no good with all 4-wheels in the mud - front E-locker engaged or not. But, once one of the front wheels got a little bit of traction on grass, the front locker would pull the jeep right out.
Don't know if True-Trac in the front would've been that effective under same scenario. Of course SMB would be much heavier.