It's a great method for someone who wants to have some fun.
I have just got a few results in front of me at random. These are starting prices of jockeys' second winners and third winners on the day:

11th. April
Canterbury(night meeting)
J. Sheehan 4/1
J. Sheehan 5/1

Moonee Valley (night meeting)
----

13th. April
Flemington:
B. Fenech 11/1
S. King 7/1

Randwick:
-----

Eagle Farm:
S. Galloway 9/4

Cheltenham:
D. Carney 5/1

20th. April
Doomben:
M.Dracos 4/1

Morphettville:
D.Oliver 10/1
K. McEvoy 6/1

Flemington:
B Prebble 5/2

Rosehill:
R Quinn 11/2
D Beasley 5/1

27th. April
Moonee Valley:
V Hall 10/9

Rosehill:
D. Beadman 5/1
C Munce 10/1

Doomben:
S Galloway 9/2

Victoria Park:
T Creek 7/1

I thought it would be interesting to just post some random recent results. (I do not have the time to check how many bets there would have been at these meetings.)
If the method is used without any refinements or form analysis it will probably have to find quite a few jockeys' second winners for the day at huge odds.