[userbinator]

Meanwhile it's pretty trivial to prove that some code is derived from some other code or some internal docs.

There are only so many sensible ways to do things. Straight copying would certainly be stupid but I think it won't be provable unless you decide to include specific aspects which would not be possible to discover through reverse-engineering, and it is likely such things wouldn't affect emulation anyway, so obviously as an emulator developer would be of no real use.

tl;dr: people are smart.