Certainly, but not so well instrumented that the dispatcher can tell where every car is. In long trains, there is enough slack in just the couplers, that the length of the train can vary by far more than one car length.
What is known in the business as “margin of error”. I’m sorry, I just don’t see any use for quantum navigation on railroads. Trip switches driving signal lights alert dispatchers and drivers when a piece of track is occupied. Trains are not supposed to pull into an occupied station. Casey Jones tragedy resulted when a train stalled on a track ahead of him, and he was exceeding the speed limit to arrive on time after a delayed departure. Even without radio communications, the conductor of the other train should have deployed signal flares in plenty of time. Accounts vary, but Jones’s fireman survived (”Jump, Sam, jump”) and testified that they did not see signal flares. In the end, the Illinois Central Railroad blamed Jones. (”That’s a good engineer a-lying there dead”)