I think we need to refreshen up on physics 101. It in fact does not take less force to move an object once in motion. The inertia of an object is predicated by its mass not its speed. Without the added forces of wind resistance, rolling resistance, gear friction, all of which compound and increase the forces necessary to accelerate an object, the mass and therefore the force necessary to change that object's speed stays constant. This is within the realm of cars of course and not particle physics. So in our car scenario it will take more force, more torque, to change the cars speed at 50 miles an hour than at 20 miles an hour due the increasing in air, rolling, and gear resistance but the mass and therefore the inertia will stay the same.Despite the fact the rest is all valid, this is what needs to be highlighted, as yes, it does take less force to move an object that is already moving. Static friction is what we are dealing with here, and the amount of force required to move an object once it is moving works on a downward curve (assuming the plain we are moving across is indeed flat and level). Our cars already know this. It takes a lot more fuel to accelerate up to cruising speed than it does to maintain cruising speed. Ergo, if we already have a part in motion, adding increasing the amount of force to it will cause less of a peak burst of static friction, thereby decreasing any load pressures.
Again, when it comes to the TC though, it's all moot, since it's hardly the weak point on most people's setups. After doing some price research, the twin screw setup isn't something I'll be going after anymore either.
And what may I ask is a "peak burst of static friction"? This might be the first double oxymoron I can remember seeing. And how does the static friction of a contact patch impede the rolling of a tire? Wait, I know the answer to this, it doesn't. Static friction or simply friction as it is commonly called allows the rotational force applied to the wheel by the axles to be transfered into forward motion.
But this is beside the point as my original question was related to whether you thought the driveline suffered more stress from a given torque at a lower rpm.
I am curious what has influenced your decision on the twin screw? Was it cost, ease of installation, torque curve, tuning?