Yes hes right. When its sparked it changes it until it passes. Its almost like a layered element except its not there but the game replaces it when the spark passes.
Yes, SPRK(TTAN) let's pressure through. This combined with the loop spark bug creates a deadly combo that destroys most of the pressure shielding in bunkers. Only if there was a way to make SPRK(TTAN) spark proof without messing up the code...