When I did heating tests. "Eternal Darkness: Sanity's Requiem" really worked up the Ccube fast. Faster than any other games (metroid prime, RE4, Collectors edition, etc).
Whenever I put in Eternal Darkness on the Ccube, it got way hot, faster than with other games. Never compared it to TP though.
If anyone does any game-heat comparisons, head over to the gamecube cooling thread to post your findings. Probably doesn't matter too much in the long run.