Some horse don't handle the same track all the time.
When FL used to open in March, we had DRF TVs of 25+ for sprints and 40+ for routes. Pace times were 49, 115
Later in the summer, the TVs were 10,12, and 20, 22. Pace times were 46, 113.
You can adjust anything - I can adjust my uncle to make him equal my aunt. But the horses can't be adjusted. One of our better trainers used to run his horse in the spring and fall, giving them the summer off.
The number one rule of mine in racing is I am betting on living creatures who have moods, feel pain, joy, have minds and think with them, NOT mathematical equation results.
No one knows everything and half of we do know was probably mis-calculated. Our only hope is there are enough mistakes made to cancel each other out in the long run.