Yes, I would normally not use any conversion to a scaled rating like a 100, as I don't want to compress/distort the actual time differences between runners.
Using those tables I posted the true science behind it is using multiple Regression, Same as greyhounds fundamentally those runners in the top quartile will actually be specialist at their distance, so example the HV1000 cohorts might only be good at that distance but within that group are another set , that need a bit further, so using multiple regression you include the Run Home sectional when your doing your regression, so Y is final time ST1200 , and now for X axis you use HV1000 final time with F400 time , so then you start separating out the speedy squib types, but for HV1650 you will use the first say 800, with the Final time and then you get an optimal formula, but again I also use a sectional weighted TV which then is just an adjustment figure which could be added or subtracted from a Par time either LR adjusted or left raw at the same form line distance. But as you venture into a proper database you will get those opportunities to test things, I mean fundamental testing not like back fitting data, which you will get a chance to do as well