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Recently I've witnessed some very trigger-happy down-voting on answers that had only just been posted and were still in the process of being edited. In one case I had just posted an answer with a couple of minor mistakes and within the 30 seconds it took me to edit the answer into shape I'd received two down-votes (with no explanatory comments of course). I've seen this happen to other people today too, so I don't think it's just me feeling victimized. The result of this knee-jerk down-voting is an otherwise useful answer which might as well be deleted, since no one is going to take much notice of an answer that already has a -2 rep.
So, a possible feature-request: disallow down-voting (or perhaps any voting?) until, say, 30 seconds after an answer has been posted or last edited ?