It's just a spam deterrent, not a spam proof tactic. Hardnut spammers can and always will find a way. It should cut down on the volume, though.

The rule is also intended to prevent new registrants who like to 'depth charge' the forum with massive multiple threads from doing so. Too often we have had ideological extremists and/or trolls register and then immediately create 7, 8, or 9 extremely crappy, partisan and/or obnoxious threads in our most popular subforums in order to overwhelm and dominate the forum and effectively control its content. These types then often abandon the forum shortly thereafter to patrol and depth charge elsewhere.

With this rule, real conversationalists will join the discussion and quickly get their thread privileges. Those who are only interested in doing what I explained will go elsewhere. As stated, real conversationalists who have just joined can ask the mod squad for permission to post a thread if they really feel the need to do so and we will screen the proposal and the poster to approve or deny it. Indeed, some decent potential poster may decide not to join us because he or she doesn't like the rule, but there are pluses and minuses for every move made. IMO, the pluses of this rule outweigh the minuses.