[VomisaCaasi]

Seems as if it isn't that hard to bypass the "trial" period of HN. In addition to minimum karma requirement, applying 3 months of newbie time would probably be somewhat helpful as well. If the user has earned his badge of negative voting after the end of the rookie period, his understanding on the site has matured to point where he knows where the site is at, and he would be more than willing to keep it that way.