I think this is a great idea; you just put a "group" flag that we can click on new stories, and the context should be enough to know which submissions to group.

I think this is a great idea; you just put a "group" flag that we can click on new stories, and the context should be enough to know which submissions to group. Limiting them only to new also avoids the urge to just group all resubmissions, create ongoing topic threads, etc.