Google recently shared that they have been hard at work on updating their algorithm to catch sites that are overly optimized. They expect to roll this out in a few weeks to a few months (but speculation is that it’s coming sooner rather than later).
So what I am hearing is that too much SEO is a bad thing (not exactly a newsflash but now they are specifically targeting it) and not enough SEO is also a bad thing.
Too much SEO = no rankings and exposure
Not enough SEO = no rankings and exposure
Just the right amount of SEO = Rankings and Exposure
SEO best practices with some common sense and a good look at your site from a user’s perspective. Google should be able to clearly detect the theme of your site via your optimization but your users shouldn’t feel like they are being hit in the face with your keywords.