eMACaRe,
I think you have got your logic the wrong way round - CFMU plan and issue slots and routes on the flow rates given to them by the ANSPs, they do not dictate how much traffic each centre or sector can take (as they do not know the precise staffing levels). If someone tells them they have a zero rate then they cannot plan traffic through that airspace.
Yes, they may have the overall picture but if someone says they cannot take any traffic then CFMU has to plan accordingly!! They can only work wih the flow rates given
