Personally I wouldn't be very comfortable with that. Aren't the cheat codes considered property of id Software? Or are they part of the source code now and therefore GPL?
I didn't realise that many people would be against changing the cheat codes. I respect this decision, but I still believe that honouring project contributors would be a nice thing if it was ever decided to change the codes. It's not like FREDRIK, ESPI, SCUBA etc. are hard to memorize.