I would appreciate people who claims that "the author does not know Lucene enough" to send a Pull Request, where Lucene is configured to do the same thing that T-Wand does, that is to guarantee documents containing more query terms to rank higher than those containing less query terms.

To those who says "I like Lucene because it does Tf-idf", please be assured that T-Wand also does tf-idf and uses vector space model.

To those who say "T-Wand is just Wand", please be reminded that you are just repeating what the article was saying. Of course T-Wand is Wand, but you miss the technical contribution of T-Wand, which is clearly laid out in "What's new in T-Wand" section of the article. Of course, it is understandable if you are not able to judge the merit of that contribution, for that's the job of the peer review panel, which I do not expect Hacker News readers to be. This work will be submitted to a peer reviewed conference with more experiments added and all trade-offs discussed.

This may come as a disappointment to some, but the paper will not have a comparison with Lucene, for it would be scientifically unsound.

However, it should be easy for Lucene to add T-Wand as an option, and I do hope so.