single or multiple posts on homepage

[ichl13]

I installed clickbump on a couple of my sites and it by default it only displays a single post on the homepage. I thought i'd try it out on a site but was wondering what you think should happen to the serps. Will it go down?

originally it had 3 posts on the homepage. One that is really optimized for the keyword, one thats moderately optimized, and one that wasn't very optimized.