tedster - 12:59 am on Mar 4, 2013 (gmt 0)
Here's the kind of question I'd ask: Is there a user benefit to placing the keywords in boldface? Would it make the page's communication clearer?
Google's algorithm today is trying to understand useer interaction with your website, not just trying to add up the various ways keywords are used. In older days (especially the 90s) algorithms working in a more mechanical fashion, like walking through a checklist and assigning points for each kind of usage. Today, things are much more subtle and you are well off to put your energies toward enhancing customer/user experience.
I'm not aware of any negative effects. However, there might be if you go over the top.