OK, I'll jump into the middle of this, which looks like it may not be a good idea!
If the diff fully locks and makes it one rigid transfer case a'la 4WD truck (which the drawings make it look like it does), then you do get 50/50 torque when all four wheels on the ground, and 0/100 if the front axle is completely off the ground. I'll make a better explanation, and if you guys are really nice maybe even an animation.
