Sorry, I forgot to put in my previous response that I would reiterate case studies & marketing plans are two very different things.....marketing plans are unproven strategies, whereas case studies are studies of actual successfully implemented business/marketing plans. Look at definition 2 in the link below.
https://www.google.com/search?q=case+study&am...p;ie=UTF-8
and this from Wiki....
https://en.wikipedia.org/wiki/Case_study
We can agree to disagree if need be