I kinda understand where your going, although I do not agree that it is any less accurate- It is more accurate, and not just in precision, even based on a 100mhz engine.
I go back to this argument, though worded slightly different;
Car A, crosses the finish line at X.011 (Real-Time).
Car B, crosses the finish line at X.019 (Real-Time).
Car A finished before Car B, and this would be 100% accurate.
A simulation engine, running at 100mhz, would detect this 1 of 2 ways, either both cars get a time of X.01 or both cars get a time of X.02. It depends on how the simulation is checking previous versus next positions... However, for sake of argument we will pretend this engine is set up for X.01, truncating the remaining time.
Each car now finished at X.01. (Simulated Time). With my segment check you can get the exact time the user crossed the line, not only more precise. The only accuracy you are 'losing' is due to acceleration / braking forces within that 0.01s that occurred. You could even include this with an avg acceleration over the frame - which would make it perfect to the engine capabilities.
My point here, is that how is considering both cars to be X.01 more accurate than detecting the exact time X.011 and X.019? As long as the engine is _always_ doing the same thing, and it computes the same time every where, which it should do automatically - then I do not understand how truncating each time to 0.01 is more accurate in any regards.
What I do understand is the slight loss of accuracy from not interpolating the acceleration. This is even possible with a little more effort and thought, though I don't think that is needed to achieve higher accuracy than we currently have. I do agree that I do not want some randomly created, higher precision values. But the calculation would always run the same, for everyone, and would be part of the engine. I would like to hear why your thinking that 0.01 is more accurate than (a correct implementation of) the interpolated time calculation.
Afterall, if the simulation engine is running at 100mhz, the car/object will move linearly during each given time step.