Frankfurt - Fulda is a haviest route in TSW history(to be more precise, the section between Hanau and Frankfurt). So I want to tell you a story related specifically to this route. -DX12 a prerequisite for working ini-adjustments. Improvements that should reduce stutters and improve performance. Streaming is the major anti-stutters booster, but streaming is eating your VRAM. To much for the Frankfurt - Fulda route. Running from Fulda, right after Hanau, I start experiencing massive FPS drops - 7-9 FPS for 30-60 seconds, even on pause. VRAM is full. I deleted all of the ini-adjustment lines(default ini-file) and run again. So the only thing which left is -DX12 parameter. 7-9 FPS for 30-60 seconds, but now in Frankfurt Sud, instead of Hanau. I deleted -DX12 parameter from the game launch settings. So? There is still free VRAM even when you entering Frankfurt Main station. No more 7-9 FPS. If you have 8 or less VRAM, then Frankfurt - Fulda isn't your route for -DX12(even without any ini-adjustments). Hope it helps someone.
About DX11. Even after 2 full runs(in each direction) performance are 100 times worse than DX12. Sorry, DTG, this game is awfully optimised by default. Those ini-adjustments authors are really do something, but you've done nothing after all this years. My FPS counter is going crazy, it never stops at some count. I don't see such unstable frames count when DX12 enabled. Even when the game paused I see every possible numbers between 52 and 75. In every other game where I encountered low FPS - it was a stable low FPS. Stable 50 FPS, stable 45 FPS. But not this freaking circus, when the counter frantically twitches showing random values.