What if the most of the user's messages are low value posts?
Not sure where the issue lies.
I would say unfortunately you still need to report each post independently. You also should still look at each thread and ensure that it is a low value low quality reply for that thread.
I can't say I've ever targeted users post history. I tend to find a thread and go through that. I'm sure in doing so I've reported the same user multiple times as spambies tend to be creatures of habit
Yeah I keep mine open as I go along, that's how I caught my faux pas lol.
The spam tends to bleed together and blur the lines between posts.