No, no, no.
If he doesn't know how to type without looking at the keys, take a letter opener and pop off a few of the them and switch them - my personal favorite is the switch between the "I" and "U" keys and "R" and "T". I did this once to someone that felt the need to put passwords on everything and it ruined his entire day since he couldn't get into anything he protected.
Also, buy a small container of whole milk. [pint size works best] Let it sit out for a few days until it's almost stinky and sour then put it in the back of his desk drawer [the larger one that holds file folders is perfect]. The smell will spill over into everything in the desk - and trust me - that smell lasts a long, long time.