Are there any rules

.... against making your hand smelly before using it to face-guard an opponent Battier-style?

DeMarcus Cousin's comment re: "wind from my hand hit Griffin" made me think of it. What if he really put some "wind" on his hand before that possession? Won't last long but might be a decent crunch time strategy for an important possession, adding an olfactory component to the defensive effort. Also, even if there are rules, violation can be difficult to detect.