Your musing about 2-way links reminded me of the short-lived "webhooks for backlinks" trend, which didn't last long before spammers found and abused it. The id

Your musing about 2-way links reminded me of the short-lived "webhooks for backlinks" trend, which didn't last long before spammers found and abused it. The idea was that you had a well-known webhook location, and when people linked to your blog post, they'd ping your webhook with their URL, and you'd display it under your blog post as a "backlink". If that's obviously a way to inject marketing spam you'd be right, but I swear this stuff got quite popular before being overran. Unfortunately google is now so bad, it's impossible to find genuine history of the phenomena I'm describing, so I just have to trust my memory that I'm not inventing a past that didn't exist.