The awful thing is that since it's Nietzsche, my automatic reaction is to not even bother trying to figure it out; his overall philosophy is about as unchristian as you can get without actual baby-eating. But the conscience is a subject I've never thought much about, and even if N is wrong, it's at least an incentive to consider an aspect of how we've been made.
Aaaargh! I had a nice, long (sorry!) answer here, and accidentally cut most of it while pasting in a link!! ;_; Sometimes I hate my brain. *sigh* And now it's time to get ready for work. I shall attempt reconstruction later, I shall.

Grr.
No need to apologize for long answers! If you ever do manage a reconstruction, excellent. If not, well, I'll just have to do some digging on my own, which would most likely be a good thing. :)