The existing system, a question that is closed as a duplicate automatically redirects users who aren't logged in (most users are anonymous google users) to the question that is the duplicate target. All of the questions that target that duplicate or mention it in another post are listed in the 'linked questions' on the sidebar.
If it truly is not a duplicate question, then it should not be closed as a duplicate. However, many people asking new questions either don't search or are unaware that their question actually is that other question.
Leaving a question open doesn't help any of the google users and instead makes it harder to find the canonical answer to the question as little tidbits of information are scattered around.
If the canonical duplicate target is insufficient in answering the question, add an answer to it that does a better job than the other answers.
