You got me on the no clock stop 2.
Not sure I understand why CHMP would ask that question in the first place. 'At the very least (if not already asked) "how would we benefit from a confirmatory trial?" should have been or is anticipated to be a question from CHMP.'
If CHMP decides that a confirmatory trial is required, they have already made that evaluation.
If CHMP decides that a confirmatory trial is not required it is because they think the drug benefits are worth approving.
A confirmatory trial is used to address weaknesses in the data of the application. So if CHMP is asking that question they are really asking, do you think that a confirmatory trial will make up for the shortcomings of the data if we give you a chance to save the approval?
The answer to that postulated question would always be "yes, we think the trial will show that drug is worthwhile".