I submitted this link [0] which was on the HN homepage a couple of days ago and the results that I got back were more either the least important bits or in some ways implying the opposite of the article, so either the writing was really bad or the algorithm needs some work.
Submitting a "simpler" less-ranty article [1] was even less successful, leading to paraphrases of less-important sentences as the results.
Then I submitted the BBC article from this morning about Philae [3] and received much, much better results. I think it works best on articles that have single sentences that clearly sum up the gist of the post as a single, hard fact and doesn't work with anything that works towards logical conclusions or tries to build an argument. Which makes sense, because this isn't an AI and can't actually deduce anything.
0: https://neosmart.net/blog/2016/on-the-growing-intentional-us...
1: https://neosmart.net/blog/2016/when-is-the-2016-retina-macbo...