anchor text of Internal links, to optimise or not?

Hi guys, in Neil Patel today's blog, he talks about penguin 3.0 and how to avoid getting hit from.
In the article he suggests to get rid of any exact match and over-optimized anchor text. It is clear to everyone that it's right to do this at external links. But what about internal links? It seems nobody has had a answer to this question.
As far as i see, since it's my website, i can do anything i want. What do you think?

 

Exact match is equivalent to general term which means it has high competition and there are some optimizers that are using over optimized keyword to get rank on search engine which has no effect now in the often changing of algorithms. A good example is the Google Hummingbird it is specially designed to provide meaning to the search query of the users and not by word by word information and as a result it will give the right data for the users that they are expecting to show from the search results.