Nothing they got the point of. Essentially manufacturers use security through obscurity, put in a tamper proof screw in and most people who aren't capable of doing the repair won't have the correct bit and will understandably not attempt to muck around with whatever it is.
Why dude wants to argue with a master tech about tamper proof bits purpose not being to resist tampering is beyond me, next they'll argue how people movers aren't meant to move people but rather to shift lifeforms from place to place....