I had a ASP.NET page with HEAD as server control similar to the following:
<HEAD runat = "server">
<link rel="stylesheet" type="text/css" href="WebjetStyles.css?v=<%=AssemblyVersionNumber()%>">
The first server function was called and executed successfully, but the second Code Render Blocks located inside a parameter of link element, wasn't considered as server code and literally was copied to client HTML as <%=AssemblyVersionNumber()%>
Only when I removed runat = "server" attribute in HEAD element, the second Code Render Block was executed and rendered to HTML correctly.