I don't know how feasible this is, or how easily it would be prone to manipulation. Thoughts are this though. What you type into a new post gets run through the search function. If it hits a certain number of responses, you can't create anew post on that subject? Better ideas and refinement are welcome.
Add a mandatory auto search function before you can post in forums? 7 votes
A lot of players want answers on the forums and it's best to let the discussions dictate if the thread gains steam, falls down the page, or gets merged if the discussion proves similar to the existing threads.
10 dooku is op thread
294,254 poe is op thread
186 FOTP is op thread
10 threads about nerfing someone besides who I listed.
Bariss healing through immunity
Who is mol ezila
Why can't I upgrade abilities
GW is to hard
GW is to easy
Please add Yoda
What characters would everyone like added.
That's all I can think of top of my head. I'm sure there is plenty more I see but these you see everyday, with different posters starting them.