Even the ability to go to the top-most node from a nested comment would be handy. I often go read someone's comment on a topic, but when I get there, I have no idea what they're commnenting on.
Something like this was proposed a while back, japhy, and it sounded good to me. If I remember right, the request was for a "jump to top of thread" link on each and every reply node, but that it would add humongously to box utilization (and to response times), so was shot down.
I'm no DB guru, but suspect your idea might have the same show-stopping drawback. If I'm wrong, doubtless some fine Monk will set the record straight. 8^) If I can dig up the thread, I'll add an Update:
And if that could be thrown into a sort of tree on the Newest Nodes page, it would be ten times clearer than now. Right now, it difficult to follow a couple of comments even though vroom has provided a nice sort of next link in the node that you click. An organized, almost graphical tree could lead us in the right direction. Perhaps the "show no levels beyond x" option in the user settings could be adapted here. Just a thought. I don't know how difficult it would be to come up with something like that; vroom has certainly made a great website as it is!