We had the same issue so instead of doing this we dropped a real quick aspx file in the inetpub\wwwroot directory called default.aspx. Here's the code we used:
<%
Response.Redirect("https://Servicedesk/ProcessManager")
%>
This has been working great for us so far. I don't know what else it might break so we made sure that we used the FQDN here and in every instance during the installation where we might have needed it.