True the rules don't limit how often an issue is reconsidered or changed. However I think it is the duty of the BOG to use a steady hand at the helm so that sailors can plan their purchases. I'm due for a mainsail soon and will plan accordingly.
I characterize this as you wanting to be able to compete in PHRF while sailing an occasional NA without buying an extra mainsail. I want to hold down costs to help my one design fleet survive. Around here the J/35 and J/80 fleets are growing while the J/30s have shrunk to about 10-12 active boats.
I don't care what sail material is approved but do care about the impact of cost, as noted above. Clearly this would be a more expensive sail and in my one design fleet no one needs one. It could be that a sexy expensive mainsail will attract more interest and increase activity, though I doubt it. I can afford a high tech main and as noted above would get one. The question is will the rest of my fleet pay the premium.
Here's an idea. My fleet passes the hat with each member pitching in $200 apiece, or better yet we assess the entire class $2000 over five years divided by the number of members. Then every five years spend $2000 to get a class mainsail that one lucky but recalcitrant PHRF racer may use annually by lottery at the NA's. That would be less expensive in the long run.