[DougWebb]

if it's effectively a duplicate then it's helpful to consolidate the answers in 'one place'

To do this, they've already got the tech to identify similar questions. They should just leave all the variations of the question open, and have a prominent "Similar Questions" list displayed for all of them. That would encourage question titles that express what makes them distinct from similar questions, and give people the option of finding the most appropriate variant and getting an answer for that specific variant.

[shagie]

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.