A Story of Persuasion and the Gunning Fog Index

Last blog post, we talked about the Gunning Fox Index. As a refresher, the Gunning Fog index is a measure of how well the written word will be understood by its intended audience.

We've also talked about the Psychology of Persuasion in the past: The long and short of it being--people are persuaded in different ways (social proof, data, experience, etc.) so one specific style of argument won't necessarily sway everyone in your audience.

This is the tale of a client, a presentation, a Wharton MBA, and how we used the Gunning Fog Index to make a case for simplicity.


Several years ago, we were helping a client (a major international Fortune-50 hospitality company) with their executive presentations. The presentations were written out and would be read off a TelePrompTer. Each executive wrote their own presentation and our job was to vet each one, suggest improvements, etc. One particular client was the VP of marketing.

She was delivering her marketing plans for the year at their annual event. Since they were going in a new direction the material was going to be very relevant for the audience (made up of Hotel Managers with only a cursory understanding of marketing and marketing terminology).

The first draft she gave us was a highly detailed examination of their marketing plan. It was well written...

... if it had been designed to appear in the Harvard Business Review.

But it didn't hit the mark for the audience. It was full of jargon, and was designed for READING not for spoken comprehension. (The brain can process reading material more rapidly than spoken material--we read faster than we can speak.) We've seen our share of presentations and are pretty savvy at understanding marketing speak and strategy--but even we had to re-read the presentation several times before we fully understood the gist of the material. Clearly there needed to be a re-write.

We highlighted key areas that should be simplified (the document had more yellow than white) and returned it. The second draft was slightly better--but only slightly. Some of the jargon was removed but it was still thick with content, huge words, and complex strategies (and sentences). It was a challenge to read and it was going to be a bear to listen to.

We sat down and had a heart-to-heart discussion with the client, but she didn't seem to grasp the need for simplicity. She stated: "Well, this is awfully clear to me... I think we're okay... I really do."

We were discussing the issue with her administrative assistant, who empathized with our plight, and she was also trying to help her boss "see the light".

Clearly, the way we were presenting our feedback wasn't persuading her. We asked her admin to tell us more about her. She explained that her boss is very bright (MBA from Wharton), very passionate about her job (that was evident in her presentation), and that she is very statistics-oriented. Statistics helped drive her decision making. Looking at her presentation, you could tell this was true. There was an abundance of data and charts. Clearly, numbers ruled for her.

Ah-ha! That's when the light bulb went on for us. We needed a way to communicate how her complex presentation was making it difficult for the audience to understand her message.

Enter the Gunning Fog Index. For someone statistically-minded, it the simple tool (and equation) used to illustrate how difficult her speech actually was to understand helped her overcome her own familiarity with the topic and look at the presentation with more objective eyes.

For the record, her first REVISED draft was so high on the Gunning Fog Index that it was at the comprehension level of a 4th year COLLEGE student--not at the level of a 7th or 8th grade HIGH SCHOOL student, like it needed to be.

By presenting her with a way to measure the result she was able to simplify the presentation and communicated the key points in a very clear manner.