Many will dispute this, but a few weeks is all it takes.

Disclaimer:
you have to differentiate when and where you are betting.
Your system may (probably will not) perform the same in Metro races as in country or prov. races.

Forget about the "thousand" races needed to prove etc. if you don't produce profit short term, there is no reason you will be in the long term.
Big bank only means you will lose a lot more but it takes longer!!!

Day to day yes, you can be up and down, but if you are losing all week, barring unforeseen conditions circumstances, then my friend the system is a crock.

Good luck