I wonder in this case whether it was a false positive. Lots of people want to support a project like this and it's fairly natural to email people and tell them that the link has been posted.
The only reason I don't do that any more is that someone told me about the voting ring detector.
It's a Kickstarter about a Django framework that a large amount of the community have a (vested) interest in. So of course this group of people are going to upvote it, just like node stuff gets upvoted by node people, Ruby by Ruby people, etc.
I wasn't making a statement about human intervention at all. One minute it was doing well on the front page, the next minute it was gone. I noticed that something disappeared/yanked/punted/hid it.
I guess this sort of protection can be helpful, but I hope that it doesn't keep other high quality but less known content out. DRF is popular enough to overcome this false positive, but I wonder if some other lesser-known (but interesting) stuff would be.