To or not to, that is the question

I recently discovered the idea of E-prime, a variant of normal English that leaves out any instance of the verb to be. Linguists and philosophers argue that this simple omission makes language more forceful and less obfuscated.
I started wondering if this meant that you could judge the forcefulness of a text from its E-prime percentage, which I defined as the relative amount of instances of "to be" in a piece of text. I wrote a simple perl script for it and ran it through a number of books:

Work	E-prime percentage
George Orwell, "Nineteen Eighty-Four"	4.73 %
Ernest Hemingway, "A Farewell to Arms"	4.31 %
JD Salinger, "The Catcher in the Rye"	3.51 %
JK Rowling, "Harry Potter and the Philosopher's Stone"	3.25 %
Stephen King, "The Shining"	3.19 %
Stephen King, "The Green Mile"	3.15 %
Salman Rushdie, "Satanic Verses"	3.15 %
Jack Kerouac, "On the Road"	3.01 %

Interesting results: it seems that classic literature tops the chart, and that Orwell, despite his abhorrence of manipulative language, obfuscates more than he might expect himself. Note how popular books, with a lot of action and less contemplation, have lower E-prime numbers. The most interesting item: On the Road, a vibrant book full of activity, considerably lower in rank than any other book.
Note, incidentally, that I wrote this entry in E-prime as well.