[walexander]

It seems like a lot of flame wars could be prevented without a pending comment feature, or at least a watered down one.

If a comment is particularly offensive/offtopic, it is already downvoted, eventually greyingout. To prevent flame wars, the reply button could simply be disabled on those comments, or in comment threads with high vote volatility (high numbers of up and down votes on parent comment). Vote volatility could indicate a flamebait worthy topic, and the reply depth could be limited based on the volatility.

Similarly the reply button could be pulled when two users are chaining long reply threads alone.

Perhaps with higher levels of karma, the reply thread depth is relaxed for those particular users.

Modifying reply access should prevent flame wars, but if there is still a desire to police the content more, then I think a "flag" button is more effective. If enough people flag your post (regardless of your karma), it could be placed in a type of quarantine area and then be pending until someone with the karma privileges decides to moderate it back in or not. I believe this is what reddit does, though the comments must be approved by mods rather than users.