I think enough people want that kind of TL;DR that it's reasonable to put one right up front. I see a similar sort of thing with DIY projects, where they tend to get better attention if the first picture is the finished product, and then it works you through the process. It's partly to placate people who only want to see the finished product, but it also gives enough of a hook to everyone else that I suspect some people will read the article who otherwise wouldn't.