[Excerpted from Wikipedia entry on SAT]
In 2005, MIT Writing Director Les Perelman plotted essay length versus essay score on the new SAT from released essays and found a high correlation between them. After studying over 50 graded essays, he found that longer essays consistently produced higher scores. In fact, he argues that by simply gauging the length of an essay without reading it, the given score of an essay could likely be determined correctly over 90% of the time. He also discovered that several of these essays were full of factual errors; the College Board does not claim to grade for factual accuracy.
Perelman, along with the National Council of Teachers of English also criticized the 25-minute writing section of the test for damaging standards of writing teaching in the classroom. They say that writing teachers training their students for the SAT will not focus on revision, depth, accuracy, but will instead produce long, formulaic, and wordy pieces. "You're getting teachers to train students to be bad writers", concluded Perelman.