Paceline selection is important but

[shoeless]

I know paceline selection is very important but how do you know when
a horse will start to tail off.I know this has been booted around many times
in the past and I guess if someone knew the answer they would be raking
in the cash.

Here is a horse today from Parx in the 5th race 5000 claimer,take a look at his last 3
Bris Spd numbers which are impressive.Will this horse repeat today?