I think, the only useful person is he who developed this workaround, Who is Simon Owen as you can see 🙂 Some stages especially in Poland are very bad optimized there are too much objects in the screen. Every gpu are bottlenecked at some area especially in the forest.
"Try this DX hack, it may help you It will only copy a modded DX file into DR's root folder https://github.com/simonowen/dirtfix/releases" Finally It works, Hallelujah! My stuttering goes away. I can use my handbrake, h-shifter again!