I dont see any benefit to it and I saw someone else here say it just looked cheesy and spammy and I agree with that. I have worked with many sites that were built by the business owner and they always go crazy wiht highlighting the words and even make them other colors. This doesnt help IMO. I just think of it as a user not a SEO does that influence me at all? Maybe once in a while but normally no, a well placed link to something useful on another page is much useful for a user.