No, i won't pester you with historical outlines on the C&C. Let's get to the point.
Sometimes developers insert elements in their games that don't really belong to videogaming. Sometimes it's morality, sometimes art, or cinematic cutscenes, or even drama, they feel fictitious, false... these xeno elements(that in this case it's right to be phobic of) are proud of their origins, cinema mostly, and they harm videogames because they seem to compensate for the poverty of the "ACTUAL" act of videogaming, interaction: they help the feeble lad.
It happens with choices & consequences too.
In many so-called RPG's, characters talk a lot, and in a cinematic way, so choices are only there, to not disrupt the hollywood value. The player gets to choose the mood in which the character answers. Also, these "choices" are VERY moral-based, they invite directly the player to consider real-world problems... and my opinion in this matter is that moral problems should come in mind post-lectum(after the gamer-over), when the player is re-thinking the game, not at the same time.
There's many more elements that don't belong to videogames, the actual videogame seems to happen only when you shoot and kill and jump, because, hey, that's what games are about, no? and they can't evolve, They can borrow things from books and cinema(cutscenes, intrigue, love affairs, suspence, sexy expressions), but the actual game is still mario and it will always be like this.
But interaction doesn't agree with this. It demands a challenge be given to the player because that's what's unique about videogames. Story and drama(a blessed gift come from the Gods) BEND, graciously shift their shape for interaction and are transformed into something unique as well(just as it happened with theatre and epic tales when NOVELS were born in '700).
So what happens, in many cinema games, with C&C?
-the player picks any choice he likes, they're all there, easy to make, they're dialogue lines, or nuke/don't nuke, kill/don't kill.
-the player knows videogames tend to be movies these times, so he's not afraid of consequences, they will never hurt him.
what instead SHOULD happen, when C&C's are under the enlightened dispotism of interaction?
-the player can still choose easily BUT now he's aware that if he explores, inspecting the environment thoroughly, if he solves secondary puzzles, acquire information, seek alternative routes, the outcome MAY be better(Black Isle's Fallout).
-the player cannot choose anything he wants because consequences WILL be terrible. His character may be murdered right in the ending scene(See Laura Bow2: the Dagger of Amon Ra or CdProjekt's The Witcher, but the most shining cases to me are Ken & Roberta Williams's unforgettable adventure games).
Story, drama, dialogues etc. are transformed into something unique which is pure players' logical considerations, they become electrical impulses from the game to the player and back to the game...
which we call interaction.
When a player chooses he MUST reflect whether there's a better way to do something and he must be "afraid" of the consequences. If some such C&C system doesn't do that, it's because the designer was tempted by elements that come from other media, he/she has failed in making a REAL videogame.