Which part? The part where the professors at the San Diego State University physics department say that you can not accurately predict the sunrise/set? I thought I already covered that topic. Perhaps you should try taking your fingers out of your ears.
Any reasonably competent person would give a reference for a claim like that!
I guess I have to hunt it up so we don't have to rely on your hearsay, see in
Why We Can't Predict Sunset Times Exactly, which contains:
"So it is hardly surprising that the standard tables of sunrise and sunset times are given
only to the nearest minute. That's about as accurate as we can expect a prediction to be."
Now, would you please explain how to predict the times of sunrise and sunset to the nearest minute of
your flat earth.
If you cannot do that, I suggest that you stop pretending to know what you are talking about!