C/R with good hands for value is best when your hand is really under/misrepresented and obviously you think that villain is capable of thin value bets.

In certain situations you can misrepresent your hand and C/R river when villain is very likely to call you down based on flop and turn such as, say you flop a set or some really strong hand and there is a flush draw out - you call flop and turn to represent your on a draw (villain would expect you to raise a strong hand to protect against his possible draws) and the draw doesnt hit a C/R is really good here as villain will think a big part of your range is just missed draws - and if you show down a set after playing this way you will have some fold equity if you play your draws this way too - it will also encourage villains to check behind mroe frequently on the river which can be good if you have a medium strength hand.