There is an article over at Politico regarding the "grade level" quality of communication for last night's State of the Union speech. The author seems to think that the 8th grade comprehension level which is noted as, "the third lowest score of any State of the Union address since 1934," is of some concern. As someone who has used the Flesch-Kincaid Grade Level formula in the past I don't think there is too much to worry about. For one, the formula is a bit flawed (designed to make sure a textbook fits the grade using it) and gives the highest scores to long, complex text using large words. Someone speaking in a stream of conscious manner will score highly but also may be entirely incoherent. Clear and concise speech gets lower "grades" but this speech is often more favorable in terms of communication.
Politico seems to think that "Obama's use of simple language is in part a reflection of his audience. ... And it's part of a larger trend in simpler State of the Union language as the speech as transitioned from a simple address to Congress into a prime-time televised event." It is very much more the later—the effects of the medium. The American audience is significantly more educated now than it has been at any time in history. The figure below shows the average grade level for presidential Inaugural Addresses since 1789. The highest score ever was for Washington's first at 25.0 (that's like two Ph.D.s!). Since 1973, these speeches have averaged 8.9. As these evolved from something that most people read in their newspaper to something that was broadcast (first on radio and then on television), the communication has simplified. Eisenhower, Lyndon Johnson, Nixon, and George H. W. Bush all gave Inaugural Addresses with lower scores than Obama's 2009 speech.
This made me wonder... How would communications from Pope Benedict XVI grade out? I ran the numbers on his homilies since September. The trend is below:
The Holy Father's homilies (translated in English) have been averaging 11.6 in recent months with a high score of 15.5 and a low of 9.1. Now it is the case that these homilies are very often read by more people than they are heard in person. Translation issues may also affect the scores. It is also the case that one might expect the content of his homilies to be a bit more complex than a modern president's State of the Union or Inaugural Address.
For comparison I went back and ran the numbers on eight homilies given by Pope John Paul II during his October 1979 apostolic visit to the United States. The average grade level for these is 10.7 with a low of 8.1 and a high of 13.1.
It appears one needs about an 11th grade education, on average, to best understand a papal homily and about an 8th grade education to do the same with an American president's speech.
[Note: the blog above is written at a 11.0 grade level.]