You can also hex edit CMD.exe to override the policy disable function.
Can you get more in detail?
I always thought there was a thread running that would compare the name of the file being run against policies.
CMD.exe by itself should be just a program that has it's functions (run files, list files, etc... etc...) but once you try to execute it, it's not CMD.exe that will compare to the policy if can be ran, but rather a Security Service (A permanently running service, multi-thread, working as proxy) that will always compare you're actions against the policy set perimeters.
And I'm pretty sure it works like that, otherwise every single file would be considerably larger, it's like embedding a 200 lines piece of code in every file, no point when you can have another file that does it, then you just call it.
But share you're idea, I'm curious now!