Yes, I understand that the drivers have some knowledge of the course, but I'm not clear how much. I know all the major race tracks, from Spa to Monza to the Nordschleife like the back of my hand, because I've run them hundreds of times - perhaps even thousands of times - in sim games. When I drive a new car - or even a familiar car - I still need many laps before I can figure out the best braking points for that particular car.
The stages in DR2 are new to me. There's a lot going on in them & a lot to learn. The better I know them, the faster I can drive them. How "realistic" is it to take 4 or 5 practice runs before setting a time in the stage? Is that "cheating"? Obviously, sim drivers eventually become extremely familiar with the all the stages in DR2, to the point where the pace notes are superfluous. I do notice that with practice I get much better at hearing & reacting to the co-driver's input, even on stages I'm driving for the first time.