For the menu setting, maybe we could re-purpose the "Show Menu Tooltips" setting. Who would want to not see the tooltips? They aren't intrusive!
As for examples, two come to mind.
Player frobs some junk item: Don't let everyone think an elephant entered the room. Hold down the 'Creep' key while you move objects to avoid making a ruckus.
A guard starts searching the player: A guard is searching for you. If you dare blackjack them, get the drop on them from behind. Forget about bashing from a side or upfront, you'll only make things worse.
First one has been a thing for a while if I'm not mistaken and should be communicated; thought we had to rely on the TDM Modpack...
The blackjack effectiviness is known to cause confusion, especially on Thief players, since Garrett seemingly knows just the right spot to bash no matter the alert level of a guard. And I don't believe adding the Deadly Shadows-like animation to TDM was a proper solution; players should be able to read the situation instead of focusing on the blackjack, which sometimes you can't even see because everything is pitch dark.
Of course, the second example should take in mind a previous standard explanation on blackjacking under normal circumstances when you equip the blackjack, for example.