Full on honesty would involve walking down the street pointing at each person you passed going 'short' 'fat' 'bald', etc til you were punched. That's assuming withholding the truth is considered as bad as lying, as I believe it is in court.
For instance, if a friend is being rude to their partner, I'll generally try to stop the situation, not by telling them they're being a twat, but by distracting them, as usually they're mad and not ready to listen to reason. Then later on I can explain what was wrong about it, when they're open to hearing it.
Also, I was in debt, hugely, about 8 years ago, and my mother still asks me occasionally, 'do you owe any money?'. If I'm say £20 behind with the phone bill and paying it next week, I'll say 'no, I'm clear, don't owe anything', as I've got it under control and no sense starting a 'conversation' about financial responsibility'.