If it's a game winning Kidney Shot I have no issue ShS-ing it.
As a general rule, regardless of class I don't use my finishers on their face.. if you're already in melee range, it takes half a second to get behind them.
EDIT:
No one will stack expertise unless they change what it does.
Thus the amount on the shoulders is useless, because the avoidance negation it offers is nothing compared to how much you need for it to be usefull.
And again, it's not worth stacking to get to that point under any circumstance.