Q. As a writer that has not had anything produced and has only written on spec, is there any value at all to mentioning completed but unproduced screenplays in, say, a grant application?
Ordinarily I would say no. The only things that go on a resume are things you've been paid for, and anything that's been produced. (So unproduced
commissioned scripts, and produced freebies like student short films, both count.) The best things, of course, are produced things you've been paid for.
But if all you have is unproduced scripts, and you're applying for grants, then put your unproduced scripts on the application. It's better than leaving it blank! At least it shows you've been doing what you can.
With the IMDB, people less often ask for one's resume. But it's good to keep yours current. I like to keep my resume one page long. As I add new credits, I drop the less impressive stuff off. Ten years ago, I had some of my student films on the ol' resume. Fifteen years ago, I had all of them. I recently dropped the commissioned rewrites that didn't have directors attached; one day, Lord willing, I'll drop off all the unproduced stuff.
Resumes are not as important to writing jobs as writing samples. If an agent sends me a script and a resume, I'll look at the script first. I only care about experience when it's a question of a TV staffing job, and I want to know if someone can take the heat.
In the mean time, go work on some student and indie short films in various capacities so you have something to put on your next grant app! (Like, for example, mine!)