Generally I don't listen to suggestions from borderline retards, but in this case I think it would be a superlative idea.  Unfortunately it would be about 4 years too late to implement such restrictions, because the worst of the shitposting, spamming, newbie infestation, account farming, and all the other woes bitcointalk has seen were mitigated by the merit system. 

But if it were up to me, I'd keep newbies in jail until they either starved to death and we could hang their skeletons from the home page or they proved their usefulness to the community via a combination of IQ testing, forced sterilization, eugenics, earned merits, and probably some other vicious methods I can't think of right now because of my blood alcohol level. 

And no, I don't remember newbie jail, but I've heard tell of it from members more experienced than me.  I do remember the old scammer tag from my lurking days, and I would also bring that back.  If anyone would like to join me in a forum coup, hit me up via PM.