Gary, I believe it is a browser thing. The only way to get your browser to "forget" the link and display it with the orginal (unvisited) color is to delete that link from your browser history. Refreshing the browser reloads the page without using the cache (if you use CTRL F5), but doesn't change your history of visited sites. Since it is still in your history, the visited link color will be used.
But yes, you can override this feature by setting visited link color the same as the link (mouseoff) color.
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