It, of course, improved conversion and it turns out there is already quite a bit of algorithmic work on the topic to help tune your ad copy.
So I am a believer in the hypothesis that simplicity and clarity, in marketing anyways, is a worthwhile pursuit.
I am going to test this Hemingway along the same lines - take some longer form copy, run it through and test output.
(1) http://www.conversionvoodoo.com/blog/2010/04/increasing-site...