I didn't look at the specific question that brought this up, but I want to comment on the wider principle.
I think it is often reasonable to provide background information that you think may be relevant and useful to the OP, even if it does not answer the specific question as asked. When this is done, it's good to state so clearly. I wouldn't downvote a answer like "This is not a direct answer, but some issues you should consider are ..." assuming the rest was reasonably written, correct, and at least vaguely relevant background material.
I also agree with Steven in that to me downvotes mean bad, misleading, poorly written gibberish, or outright wrong. At least those are my criteria for downvoting a answer.
Here is a good example of what I am talking about. This does not directly answer the question, but I think (obviously, else I wouldn't have written it) it was nonetheless useful information, particularly for the repository of knowledge this site is trying to build. Whether it actually helps the OP, I don't know, since that depends on particulars we weren't given. I can understand if the OP doesn't accept this answer, but note that it did receive two upvotes and no downvotes.