I've followed GPL discussions from the sidelines for sometime, and whenever someone comes up with a 'trick' scenario like this, the standard advice is "if you'd

I've followed GPL discussions from the sidelines for sometime, and whenever someone comes up with a 'trick' scenario like this, the standard advice is "if you'd like to do that, call your lawyer". (The legal definition of 'derived works' is based in case law and is more complex than what you'd find in a FSF FAQ.)