Could this be useful for source code watermarking? (Score 3, Interesting)

Does anyone besides me think that this kind of technique could provide stronger protection in cases of source code piracy such as GPL violations, theft of codebase, etc.,? By generating visual patterns based on the occurrence of keywords (or even compiled bytecodes) a signature of a codebase could be generated that is still recognizable even after comments have been stripped out or subtle changes introduced. This could be immensely valuable in GPL infringement cases.