From my experience, this is a no-brainer:
CO don't do much for the congregations anyway, they just show up every 6 months and do not solve or give any insight to the BOEs. The only thing they do is report back the congo's activities to the branch, but they can achive the same thing using super-elders picked from each circuit that work regularly and visit an X amount of congo each year.
They already use super-elders for some pedo cases, PLUS they use some super-elders to even teach the Pioneer School along with CO, but that show they are willing to use elders to do things things that regularly CO used to do.
Biggest win-win for using super-elders instead of CO: No money drainers.