This is as much a human issue as it is a technical one.

The designers I'm dealing with are not developers. Setting things up so that they can open a template directly in a browser is easy for them. Easy in this case is Good. Requiring that they copy the template onto a web server, then pull up a form and name the template, adds nuisance work to their plates. Nuisance in this case is Bad.

If I was working with development-savvy page designers, a CGI to pre-process the template mght be an option.