That's my proposal, whitebelts can make threads and post, but only other whitebelts can see their posts.
In this scenario, whitebelts are free to make shitposts free of any thought or analysis, but they live in a shitocracy. Mods can view whitebelt threads and posts; if they think that a particular post showed some thought with substantial material, they can approve that post. 10 mod approvals means that the poster gets his yellow belt, and joins the forums at large.
A good poster could get his yellow belt in 10 posts, whereas idiots advocating unsupportable positions would be forever in whitebelt limbo.
It's undeniably net gain, goatse spammers would have to spend weeks posting thoughtful analysis to get banned in an hour, Kimbo supporters would actually have to advance arguments as to why he's GOAT, and Timmah fans would actually have to map out a plausible road for his redemption.
These potential whitebelt posters don't have to be Nostradamus, they just have to show the reasoning behind their thoughts. Just posting "Fedor by armbar" or "Brock wins" does nothing to add to the debate at hand and should not be encouraged.