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I agree with Trung. Keep in mind that any tool, including Moz's, take a one-size-fits-all approach. The tool is meant to warn you when your page doesn't follow best practices - but if there's a perfectly legitimate reason for the words to be there, don't sweat it. If the keywords make sense, by all means leave them in there. You don't always have to follow best practices. On the other hand, if you fear the page isn't ranking well because of over-optimization, there are other places you can controll use of keywords, such as the title tag, the alt attribute in photos, headers, the URL and incoming anchor text. Often, for over-optimized pages, toning down the keywords in these areas can make a difference. The one thing I would caution against is placing any text you want to hide in an iFrame, as Google is getting good at associating those with the page content. Hope that helps! Best of luck with your SEO.