DFC
I do not aggree with you with respect to challenge and response checklists. You need two people to do achieve the full measure of extra rigour that this method gives. A good example of this is pulling the fire handle. The challenge and response requires one pilot to "challenge" the other pilot to "respond" with a confirmation that the correct handle is being pulled before the action is actually taken. Your discription is simply a single pilot properly performing a "do list". The video shows proper use of a flow which then is backed up by "checking" the checklist, which is I think what everyone has been advocating.
By saying flows should back up checklist my intent was to articulate that the flow and the checklist compliment each other. That is the order of the flow should be consistant from for each section of the checklist and should be in the same order as do and checklists. This concept is unfortuantely seldom followed in the checklists I have seen at flight schools.