I created a new table in the database to associate comments to the node version they were submitted against. Now when the node renders, I only want to display comments that are associated with the specific node vid. I thought about querying the db in hook_node_view to remove the comments that don't apply, but ideally only comments associated with the vid are added to the node in the first place. Is there a better way to implement this? Can I get at the node right before the comments are added to it?
Apparently, the comment metadata populated after node_load comes from comment_node_load(). But indeed the comments themselves aren't added until view time at comment_node_view(), which calls comment_node_page_additions() which adds the renderable comments, which calls comment_get_thread() to load the cids.
So perhaps it would take adding vid column to the comment table, and then adding vid condition in comment_get_thread...hmmm.