My question about RAID 2 was quickly downvoted and closed for being non-constructive. Can someone explain why it was deemed non-constructive so that I can ask better questions in the future?
I can't speak for others, but I voted too localized.
This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, see the FAQ.
First, RAID 2 is not in common use, as you obviously are aware. Which brings us to the FAQ:
You should only ask practical, answerable questions based on actual problems that you face. Chatty, open-ended questions diminish the usefulness of our site and push other questions off the front page.
I think you'll find that since we're a site aimed squarely at professionals that have questions relating to things we do at work on a daily bases, theoretical questions get downvoted and closed because they don't really apply.
Certainly, some theoretical questions do apply to us, but a question about RAID 2 don't fit into that category :)
Basically, it's a question to which you can't get an objective, factual-backed/based answer. Too subjective. (Probably inherently subjective, IMO.)
As the close text says:
As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or specific expertise, but this question will likely solicit debate, arguments, polling, or extended discussion.