First, about the Wilderness
Anything outside of unreasonable driving distance to Los Angeles counts as wilderness. Barstow and even Baker don't count, since you could make an afternoon meeting if called by someone capable of getting you work. For some of my friends, Las Vegas, Phoenix, and Sacramento doesn't count...
Pretty much every other cubic centimeter of the universe does count as Wilderness.
My guess is that the reason for this largely --maybe solely -- stems from your ability to easily get in a room or at a lunch table with the people who might possibly contemplate working with you. These are the people who will later decide who to hire for re-writes and assignments, the most common sort of job -- and they'll go after people with whom they feel comfortable.
In this interview (you might need a subscription for that link, I'm afraid), producer Lawrence Turman says the following:
I only work with a writer face to face. There have been rare occasions where the writer lives far away and I will annotate a script in great detail as to my thoughts, after which we will have a telephone conversation to clarify any particular point. But I want to see the whites of his eyes and he mine so we can really engage in the most productive, creative partnership.
Of course, you can make it from outside L.A. but the real concern for us out here, living amongst the, um, wild deer, armadillos, and road runners, is how much harder does it make it?
I suspect it makes it significantly more challenging to get representation prior to a sale or big contest win, which means that you won't have a manager's or agent's connections to help get your spec screenplays read.
But at the just writing spec screenplays stage, and the early stages of sending them out, I don't think it's much worse. After all, our early stuff will stink anyway and we just need to get that phase out of the way.
I'll continue on with this, in particular, going over each phase of the process, but right now I collected up some other pages that talk about the chances of making it from the outside. If anyone has more links please drop a comment and I'll edit this post to include them.
The Out of Towners -- The Thinking Writer
Moving to Hollywood -- John August
More LA Relocating -- John August
I Love LA -- Wordplay
Living Outside Los Angeles -- What Are The Chances? -- Done Deal Message Board