You are trying to complicate things by comparing 2 dissimilar items.
If you wish to know exactly what time an animal took to run the complete 525 metres , then you have to keep running the tape until that animal crosses the finishing line and then seeing what time has elapsed.

Because most of us don't have access , and don't care to go to so much trouble to set up the software to do this , we find a very close approximation is arrived at using the method Tijuana describes.

You simply being too clinical again here WOOF43.
I'm surprised you actually get anything done at all.
I know when I try to get anything done perfectly , I take ages to finish the task.

I read somewhere once that second best is usually good enough.
And near enough is good enough.
I mean nobody ever gets even one Race in a lifetime perfectly exactly accurately handicapped.