Whether it's for legal reasons, the desire to keep your job or just plain self preservation. What would you love to say in the real world but really can't? Could be job or relationship or family - could even be related to running.
I'll kick off with the following:
I'm sorry if you are upset that I am apparently questioning your ability to do your job, but the truth is I, and a number of other people, have been covering for you for the last 2 months and its about time someone told you to pull your finger out and do your fecking job the way you're supposed to!
(Thread nicked from Fetch, where it is noted for some top rants)