The JFM concept will be intersting when you consider the rearcrew implications for several reasons:
1. Currently, CHF only operate with one cmn, so will need a reasonable uplift in manning.
2. Rank/Pay/Trg differences between WSOp and RM(Cmn) for the same job.
This is not insurmountable, but will be interesting to see what becomes the accepted..........
There is also a standardisation issue. What does "descending" mean again?
As you say though, not insurmountable, but certainly another opportunity for willy-waving.