It looks like ActionLink always uses calls HttpUtility.Encode on the link text. You could use UrlHelper to generate the href and build the anchor tag yourself.
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Alternatively you can "decode" the string you pass to ActionLink. Constructing the link in HTML seems to be slightly more readable (to me) - especially in Razor. Below is the equivalent for comparison.
@Html.ActionLink(HttpUtility.HtmlDecode("More…"), "Posts", ...)