TTA, this is basically the approach I take with my ratings. While my ratings have shown a profit just on flat stakes all races top rater, the results improve greatly when you use those 3 filters you highlighted:

1) Only bet when your top rater is an overlay
2) Only bet on Good or Dead tracks
3) Only bet in quality fields with enough form (No point betting a race that has a few horses with 2-3 barrier trials and one maiden win IMO, our ratings work best when the form is there to work with)

Simply applying these 3 filters enhance's the results of ratings based betting quite a bit, well at least it has done so for me. Hard to ignore the huge difference overlay's make.

I don't have my exact stats on me at the moment but basically with my top rater when it is an underlay it shows a decent strike rate (around 35% from memory) but the POT is essentially flat - because its all favourites. However on the flip-side my overlays have a worse strike rate (around the 28-30% mark) but obtain a POT of approx 70%. So far its been enough evidence for me to understand that obtaining value is an absolute key to making a profit.

Note the above is based on the approx 1,300 races i've done my ratings on sinday 1st April this year.

Yep my bettable races were a combination of 3 different ratings,
Services i subscribed to way back when i was teaching myself,
How to do form, they are currently still operating i also attended several
Racing seminars here in Melbourne and interstate who had pro-punters,
Talk about how they operated, methods, selection criteria, pricing horses,
All that plus numerous mechanical systems from Punters Choice,
Is where i am today the whole lot rolled into one so to speak.

Only took 25> years and i am still learning.

What method(s) works for one, will not work for another, all depends on,
What factor(s) you use to derive your selections and how you intend,
To back them and what actually suits each persons makeup.

My ideas are just that (ideas) some may find them useless others,
Beneficial, guess that's what makes the world go round.

How does that qoute go.

"YOU CAN PLEASE SOME OF THE PEOPLE SOME OF THE TIME"
"YOU CAN'T PLEASE ALL OF THE PEOPLE ALL OF THE TIME".

Guess that sums up most things in life.

Cheers.
Garyf.

There are stacks of things i definitely disagree with on the forum,
Just because i disagree doesn't make it right.

I usually will only respond when i agree with something makes,
It much more pleasant on the forum or maybe raise a slight,
Query with something at worst.

If i basically can't say something nice then don't say anything at all.

Guess that's my upbringing and job i had.

Sports teacher at a private school in Melbournes west.

Cheers.
Garyf.