SlideRuleEra,
I think you are taking that comment differently than I meant it. I work in product design, lots of medical electronics, telecom, consumer, etc. We routinely get customers that ask for something that has not been done before and is not easy to do. What I mean by "blame customer requirements" is that if a particular set of requirements like "must not exceed L x W x H" and "must be able to withstand X load or Y pressure" conflict and require additional rounds of design and testing, driving schedule or unit cost, that would be worth mentioning. As opposed to "hendersdc was responsible for this aspect of the design and didn't get it right so we had to make more prototypes and coulddn't hit our unit cost target".
I wouldn't have any problems giving the same presentations with the customer in the room, they should know what the challenges and risks that were realized in the design were just as well as I.