Not sure if this has been discussed before, but I want to talk about. Many people say that there are different keyword density across keywords from different niches. IMO, the keyword density is applied at global level, so it's not like the sciatica niche should tolerate more % than casino for instance. I think it has to do with the authority of site, or to be more precise, with the number of unique backlinks(RD). The higher the number of generic/brand/naked links, the better you can use a bigger keyword density. But here 2 questions popped in my head: 1. Is it actually because of higher unrelated anchors(generic etc.) backlinks which delute the kw target? 2. Or in fact that particular website it's penalized, but due to it's enourmous backlink profile, you won't notice? Because I see like this: depending of how much you optimize for that particular keyword your site gets a score. If you increase the density to a certain point, then the on-page score will increase, but if you pass that thresold, your score will get smaller which results in the penalization. But because you compensate with a huge diversified profile, you won't notice it. If not mistaken, even phpbuilt said that you can get your kw penalized just a few places. That'd make my on-page study futile. I'd have to test at different BL counts to make it worthwhile. What do you think?