Sometimes tweets show up as top stories on HN. A tweet takes a few seconds to read and vote on. So the timer idea would not allow tweet stories to get to the to

Sometimes tweets show up as top stories on HN. A tweet takes a few seconds to read and vote on. So the timer idea would not allow tweet stories to get to the top unless the timer knew the story was a tweet. But most stories are not tweets and not short, so should take over a minute to read.