I challange any one to try to come up with a march that win more then my solution - it is Amazing how effective it is.

Here is two solutions following the random path with 1 in 3 probability.

The first march:

You see dozen 1 you play dozen 1.

You have dozen 1 and 2 you play dozen 1 and 2.

You always follow the last hitting dozen and play against dozen to alternate 123.

Secound march:

Lets say you see dozen 1 then you play dozen 2 and 3

Lets say you see dozen 2 then you play dozen 1 and 3

Lets say you see dozen 3 then you play dozen 1 and 2

Until two two loses, then you wait for a fictive win and start over.

I test the second march flat betting: