I'm going to adjust my bid lower (entered wrong amount) but I have proven expereince increasing the speeds of wordpress sites, if you view my profile, I am ranked among the top one 1% of all wordpress developers on here. A lot of the times though, as wordpress is a heavily database intensive CMS, a lot of the time it is your server at fault. Do not rely on website speed scanners like yslow and gtmetrix when dealing with wordpress, they cannot analyze your server configuration which is what's going to have the most impact.