Two things LJ could do to vastly improve conversations

1) Rather than collapse comments at all, ever, go to multiple pages sooner. I've had long conversations going on on my journal where multiple people are commenting on each other, and the second the comments were collapsed the conversations stopped. Oh, a few threads staggered on, with people replying back and forth, but the general melee finished the second people couldn't browse the entire thing. It's a terrible way to display information and kills the general discussion stone dead.

2) Contra-intuitively, remove the option in comment emails which takes you straight to "reply to this comment". If you forced people to go to the thread starting at that comment instead then they'd see the whole discussion, note what points had already been responded to by other people, and pick things up there. Instead, what you get is people responding back and forth in a dialogue, not taking in the wider context.