This one. Although I didn't necessarily mean we (the gamer) should "know what our choices lead to", but rather should take into account what our choices *might* lead to, and make a choice from there.
After all, what did he (or anyone, for that matter) expect? A big glowing "if you side with him you will be Darkside! turn back! turn back! do not pick this guy if you are LS!".
There's a reason it's a ROLEPLAYING game. You choose options that you think suits your role, and then you live with those consequences. If the choice you pick ends up counterproductive to what you're aiming for, then live with that poor choice.