I think you make some excellent points.
When it comes to betting a day it could very well pay dividends to act quickly on a hunch of a bias, and I for one would not fault that approach at all. I\'m also fully confident in that you, Frank D., Jimbo66, Mjellish, Bias Bob and many others \"bias conscious\" long term followers of this game have eyes as good as anyones to spot those early - and I\'m sure it have paid you guys well in plenty of occasions.
Certainly a crucial skill, IMO, when making bets, and even if one is wrong one would in the process at least have focused ones bets on horses predicted to run in a path that at the very least is not bad! And that is worth something, in itself.
Biases exists, and even a \"mild\" bias is worthy of attention. They are even possible to predict to a degree, if one have followed a track for a long enough time and know what different weather, track maintenance etc is producing the different biases (sometimes). At the track I\'m following the closest for instance, it\'s a well known phenomenon that when they use a scraper on the dirt track and specially with a bit of moisture in the air and even more so if the weather is cold, it could produce some crazy biases favoring those inside, and on the front end. The better you \"know\" what to expect from a track given different conditions and track maintenance, the less evidence should one demand from oneself before acting on those hunches of a bias.
There is a difference though, in identifying a bias early when there still are bets to be made that day, and to look back and try to confirm it with methodology after the facts (for later use). I find that using figures to try to establish those biases after the fact, is a pretty fruitful way to go about it. If there is a clear bias either way, most of those that ran against it will be compromised i.e not been given the opportunity to run to their true ability (figure wise). If there is a outside bias, those could also produce some ground loaded figures that give those horses more credit for their effort than they deserved; figures they will have trouble with reproducing in fair conditions.