As I mentioned above (but probably didn't explained well), my suggestions for new sub-forums came from the requests and experience that came from VDH.
Some sub-forums really wanted to be a separate section even if the amount of traffic was relatively lower then other. An example was the gatherings. That section has been used for years to plan vintage dive gatherings without conflicting with others planning gatherings in other parts of the country (or world).
Having all the threads in one location had a big benefit without having to search every-time and not knowing what to search for.
The vintage tank and valves is not as important, but reserve valves and some of the single outlet multi-tank manifolds really get no respect in the modern tank section. And what I mean is almost harassment, by some that don't understand their proper use and respected place in diving history.
The vintage single hose is also a very important subsection to discuss the use and preservation of the early single hose regulators. Single hose regulators are not as collectable, but they need their own space.
I can go on and describe the reason for the 5 sections that We are suggesting... I actually started with a longer list. But thinking that it is based on just the volume or traffic, IMHO it kinds of misses the point of certain discussions.
We found that if we did not have the separate section for some subjects, the topics and the discussion were never going to occur.
This is all my opinion, based on my observations from VDH.
@rsingler , I am not sure what you mean by Classified sub-forum.
Thanks