Do we each get a daily allotment of words?

I sat with my friend - now a bestselling novelist who appears on national TV - but back then we were all writing obsessively, driven to tell our little stories, and hoping for the best - on a farmhouse porch in Iowa.
It was Halloween and inside the living room shook with dancers decked out in complex, tongue-in-cheek, conceptual costumes. The sort one imagines from MFA students holed up in Iowa trying to get books done -- and using any excuse not to write, such as making the most clever Halloween costume.
We were both finishing MFAs at the university. We were both deep into our first books. The horizon offered the pale orange glow of halogen lights and the fields stretching out before us were turned over, uneven, yet still marked by the neat of rows of monoculture corn estates.
She announced to me that there would be no more emails on a daily basis -- a habit I had come to adore of her -- lively, bright, witty missives, seemingly taken from the Victorians' habit of writing notes and sending them round during afternoon tea.
Her rationale was simple. She believed that each of us only has so many words in us to write each day. Email, she proclaimed, was sapping her strength for the important work, her book.
This statement has been much debated by the two of us and others over the ensuing years. Do we really have a finite number of words each day? Do we drain the supply via email, blogs, and Tweets?

Today in The Presidio the sky, I am dismayed to report, is once again a silver dome. The hawks have been busy since sunrise screeching and diving -- they seem immune to the weather -- putting on a show akin to Jurassic Park scenes, diving, air fights -- all terribly dramatic.
I thought of my friends words and decided to break my usual pattern of "checking in" via iPhone (four calls and three texts await me) and not even crack open email.
If we do have a limited number of words each day -- each year, each decade -- an idea I can argue both for and against -- at least today all the words go to this book, Here Is Where We Walk.