[Edit in red]I actually cant see the point in these Hank. The RDU is already isolated from the suspension because its basically bolted to the chassis so who cares how much it moves around(to a point of course) All I can see you getting is more NVH. Cant see how its going to affect handling at all.
My reasoning is now that I'm throwing more torque to the rear than Ford had intended, it will start to overstress the existing components. To prevent any excess movement of the RDU, I opted for the Powerflex Black Series RDU bushing inserts. The typical driveshaft u-joint angle limit is 3 degrees maximum up to a certain driveshaft rpm (say 5,000). The RS has a CV joint at the RDU. I don't know the CV joint angle limit maximum, but minimizing the RDU deflection will maintain a long, healthy life for the CV joint. The RS Workshop Manual lists the max articulation of the flex couplings at 7 degrees. I didn't measure the driveshaft angles at max deflection of the factory bushings, but I was able to deflect the front of the RDU by hand almost 1/2". I'm sure I could have got a higher deflection with a pry bar. After installing the RDU bushing inserts I wasn't able to move the RDU at all by hand. This greatly reduces the potential for a driveshaft failure by the added torque being sent to the RDU. And although I've never had rear wheel hop with my RS (yet), the bushing inserts should help prevent that. And we all know that OE rubber bushings don't last that long with what I've been doing to them for years. Eventually they will wear out. The bushing inserts might add some life to them. It's a test for me because I've never ran bushing inserts before.
RDU Programming tidbit:
If I don't like the extra torque for the twisty bits of autox, then I will have Kacper dial down the extra torque for just my launches only. If my tires can hold the 25% torque increase for launch only, then I will continue testing to figure out what torque I add for the twisty bits.