It has been a long time since I looked at that thread, but IIRC correctly, I participated by strongly cautioning against drawing any conclusions from it. It is bound to present an unrealistic range of results.
- It is on ScubaBoard, a forum highly overrepresented by experienced divers. Another SB forum found that the majority of participants use a BP/W setup for their BCD, and about the time of that survey, an industry survey of the scuba retailers showed that BP/Ws represented 1% of BCD sales. In my area, the vast majority of dive shops do not stock BP/Ws.
- The survey called for voluntary participation. I don't recall if I participated, but I hope I didn't, for the very reason exemplified by the opening post. When people voluntarily participate in a survey, the ones who participate tend to be at the extremes, and if one extreme is clearly bad, then that extreme gets little partitication.
- As results get published while people are still participating, later participants tend to skew their responses in the direction of the majority.
So I do not believe that any survey of ScubaBoard participants on any topic will come anywhere close to reflecting the range of behaviors in the diving public.