There are so many variables, who knows what they'll do. If there were not variables it'd be good.
Person A might estmate what they'll do on a float day.
Person B might estimate what they'll do on a fair day.
Person C is just deluded and thinks they're a world champ.
Dunno, I think estimated times with LTS is useful. My LTS is 3:49 but I don't think I'll do that in the Hounslow.