Cliches, colloquialisms and corniness in professional writing

In a nutshell, for professional writing that's top-notch, does the job and gets it spot on, steer clear of cliches, avoid colloquialism like the plague, and give corny language a miss because putting pen to paper with these is just not cricket (unless, of course, you're doing it for effect like this).

These three Cs are markers of unimaginative writing that do not belong in professional writing. They make readers feel nauseous and uninspired.

Here are some phrases I've been mercilessly cutting from some professional text:
~ they're sitting ducks
~ you have to dot the Is and cross the Ts
~ needs must
~ at the end of the day
~ when all's said and done
~ it's all Russian to me
~ chipping away
~ progress was up and down
~ like a reg flag to a bull
~ split hairs
~ full steam ahead