Ok. so we've done some research on debutants that don't win as well as their prices suggest.
Looking at yesterdays qualifiers they all lost, some at huge prices (66/1) but also some at more realistic prices.
We don't have the Betfair SP's, so although we have a 40% advantage over SP it may not be a winning lay system at Betfair SP because when we get to the big prices Betfair SP can be more than 40% bigger then industry SP. And that may be a reason to exclude bigger priced horses.
If anybody wants to volunteer to look up the Betfair SP's for the 1500 or so qualifiers so far this year then I'd be pleased to hear from you 
For now I'm going to start recording the Betfair SP's going forward and will keep a record to see how the system performs in real life as it were.
The rules I'm using is the horse is having it's first ever run, there is at least 1 other horse in the race that has had a run and I've excluded the trainers I listed on Wednesday.
I may add a pricing rule at a later date depending on the outcome of the Betfair SP research.
Here are today's (lay) qualifiers…
14:00:00 Chester 7 Right Behind You
14:10:00 Thirsk 10 Aramadyh
14:10:00 Thirsk 11 Tortoise
14:40:00 Thirsk 3 Highway Pursuit
14:40:00 Thirsk 4 Little Bruv
14:40:00 Thirsk 6 Mustamir (IRE)
15:20:00 Sandown 4 Cape Summit
15:20:00 Sandown 13 Mind
15:20:00 Sandown 14 Stampede (IRE)
16:25:00 Sandown 1 Dark Amber
17:10:00 Salisbury 1 Desert Ace (IRE)
17:30:00 Southwell 2 Quick Decision
17:45:00 Salisbury 5 Marmarus
19:50:00 Killarney 10 Tilthemidnighthour
Today's Selection
Southwell 7.00 Golden Jubilee – win bet – 6/1 Boylesports
I know from reading previous articles that you use Horseracebase, why don’t you plug these details in there because you can also find Betfair SP’s at the same time
Hi Gareth
HRB estimates what the Betfair SP will be and frankly I don’t trust estimates
Dave
Oh, I thought that the past results were actual SP’s
I think a pricing rule would be a very good idea personally as all it would take is one long priced horse to win a race and any profits could be wiped out completely. Good luck with the experiment though, would be interested in seeing the results
Hi Dave – I also found additional qualifiers? Can you check why you haven’t listed these too….
3.20 Sand Berkeley Vale
4.25 Sand Sultry Lady
5.10 Sali Smidgen
5.45 Sali Mishnah
Race you have not done?
4.55 Sout Truth Hurts and Bridge To My Heart
Thanks
Hi Andy
I just took what HRB output, so I didnt deliberately exclude these.
Dave
Just to say Dave – I think you could have a cracker here – makes a lot of sense but just need to make it manageable, odds wise I think.