Terminator 2 rules.
What kind of rules are those? Keep most of your weaponry in a hole in the desert? When it comes to transportation, prefer motorcycles? When engaging with the enemy, don't bother taking cover, just walk right over to him?
Maybe the rules regarding the T-1000's limitations? As advanced as a mimetic polyalloy is, even it can only do so much.
There was one rule that was changed between the theatrical release and the extended cut, however: the Terminator's ability to learn new things... and not be such a dork all the time... by resetting his processor switch.
BTW the mirror "reflection" in this scene is actually Arnie, Linda Hamilton's twin sister, and Eddie Furlong's stand-in, while the real Linda Hamilton and Eddie Furlong are yanking the Terminator chip out of a life-like mock-up of Arnie's head. Some brilliant work by Stan Winston (RIP) and his talented practical FX cohorts.
Speaking of twins and practical FX: Linda's sis would show up later as the T-1000 disguising itself as Sarah Connor to lure out John during the climactic steel mill scene:
My God, I know way too much trivia about this flick... almost as much as I do about
RoboCop.