Originally Posted by i_c_the_light
Only rotational speed is varied, not torque.
The 5MT cars have 3 plain old standard differentials (with a viscous coupling limited slip added on the center diff). There's a 50/50 torque split front to rear when all four wheels have the same traction just the same as there is 50/50 side to side on either axle (or on the driven axle in any FWD or RWD car).
Where you might be getting mixed up is how the center LSD works. In a viscous coupling, the mechanism centers rotational speed differences, and that's what causes it to lock up. Torsen differentials sense and lock up with torque differences, and of course the DCCD in the STi has electronically controlled locking.
So, the "active traction distribution" in the 5MT is controlled by rotational speed variance, but the torque split in normal conditions is indeed 50/50.
EDIT: And to stay on topic: I agree that it's unfortunate that it's getting harder to find MT cars (both with respect to dealer stocks an models where an MT is even offered). I disagree that there's no point in an MT on a simple commuter car. Plenty of advantages even when there's not much power or a sport tuned suspension!