Assuming AI Best Horse Pct gives a reasonably accurate estimation of a horse's win probability, and that the AI Line is some kind of estimate of the final tote odds, the grades are the most important thing of all, in my opinion.

As you may know, Grades are just an expression of the $Net. For example, A+ means the $Net is greater than $2.40, where $Net = $2.00 is break even.

I have noticed that $Net is a function of AI Line (AILineOdds) and AI Best Horse Pct (AIBHPct) according to the usual formula for ROI:

$1ROI = Odds * Probability - (1 - Probability)

where $1ROI is the Return On Investment for each $1 bet ($1ROI = 0.0 is break even).

in DET
$1ROI = AILineOdds * AIBHPct - (1 - AIBHPct)

For example for AILineOdds = 0.34 and AIBHPct = 36.2% = 0.362,

$1 ROI = 0.34 * .362 - (1-.362) = -0.51

To convert $1 ROI to $Net,
$Net = 2 * $1ROI + $2

In this example
$Net = $2 * (-0.51) + $2 = $0.97.

My philosophy is to never bet horse to win that have $Net less than $2.00. Assuming the AI Line and AI Best Horse Pct are accurate, betting such horses will always lead to losses in the long run. I focus on horses with $Net > $2.40, i.e., A+ horses.

<< I believe the Grades (A+, D, etc.) were initially portrayed as ways to find who the whales are likely to bet>>

I am not sure that is correct. My understanding is the AI Line is how the public (mostly whales) should bet, whereas the AI BH Pct is how the AI predicts the win probability for each horse. $Net/Grades are a function of both of these.

Thanks, Tom.
"I am not sure that is correct. My understanding is the AI Line is how the public (mostly whales) should bet, whereas the AI BH Pct is how the AI predicts the win probability for each horse. $Net/Grades are a function of both of these."

Ah, therein lies my confusion...I took some notes while watching the first set of videos some time back and I must have misinterpreted things.

It would be interesting to get a better feel of how often AI Line is on the mark (within a reasonable deviation) and how often AI BH is. I suppose The Neal has been devised to, in a way, unplug the potential AI Line uncertainty from the equation focusing solely on AI BH + user's own analysis. If that is consistently achieved/achievable, I see no reason not to employ The Neal at the expense of AI Line by default...especially in predicted Chaos races. If my chain of thought is correct, we're back to square one: Grades are not that meaningful after all :)

@Atakante I am sure Dave will be weighing in here shortly, but in the meantime:

Yes, The Neal uses the real time tote odds, which are of course a better estimate of the final tote odds than the AI Line is, so are better for estimating real time $Net value, I agree.

Yes, it would be fantastic to have an idea of how well the AI Line and AI BH do at predicting final odds and win percentage respectively. In effect we are each responsible for doing our own research on how it does for different scenarios, if I understand Dave correctly.

I believe the Grades (A+, D, etc.) were initially portrayed as ways to find who the whales are likely to bet on (mainly A+ and As) but I'm curious to find if anyone here really rely on those for their handicapping. It's still not clear to me what/how they contribute as opposed to say Magnitude and Rank. Any responses appreciated... — Atakante

Short version from my POV:
First, Grades are derived from pure math.

As Tom said, it is always the payoff from the "selected odds" times the hit rate.

The correct formula is (Odds x 2 +2) x Pct = $net.
"Grade" is also as Tom said; a function of the $net.
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In a perfect world, All we'd need is to bet all the A+ horses and retire to wherever we want that has an internet connection.

Here's the problem:
$Net is a function of odds x hit rate and NEITHER OF THOSE IS ACCURATE!

Still, it is a good estimate of both probability and profit, but... honestly, it takes more.

BTW, Optimum% is probably a better measuring stick in the sense that you'd be better off betting more on a low odds A+ than a high odds A+.

While there is a time and a place for just using Grade, $Net, or Opt%, the game isn't that simple.

There are complications to the entire picture. At this morning's live play session we discussed a process that I call "Using Boxes" to build systems. In the coming days I will try to find time to expand on it.