This created a doubt/curiosity in me.
Are you only looking at campaign performance directly, i.e., customers coming directly from the forum? Or are you looking at the SEO performance the forum can bring to the project?
They're two different things. If you only look at direct performance, you'll end up limiting yourself to the same users, even though the forum has thousands. Another is to look at the impact that the link/site shared on Bitcointalk has on SEO and search engines, which will improve search performance and more.
Good point. I don't know exactly how SEO works today, especially since they change the algorithm from time to time, but my understanding is that many links coming from this forum, which has a great reputation, to a site, help it rank higher in SEO. It's clear that, according to LM, there is a limit to direct referrals from here, but we would have to look at that second part you mention.