Sorry , I still not clear for this point , why cannot skip because these is option and each lab must be determined during method validation process in local laboratory. If you are confirm still need to do (can not skip) , I agree with you but I thought that I cannot complete with in this week.
11.10 Measurements uncertainty (option)
The uncertainty is determined during method validation process in local laboratory.
11.11 Robustness (option)
The robustness is determined during method validation process in local laboratory.