I absolutely agree Treadstone about the need for adaptability, and that's where PP needs to be treated with massive care.
I give quite a few public lectures on various aviation topics, and I usually use PP. However, I'm very clear in my mind that PP is a backdrop, people have come to hear me - as I could have just emailed my slides, and I keep the information very minimal or people will just be reading my slides and not listening to me.
When I'm university lecturing or delivering specialist groundschool on flight testing, I often use PP, but I virtually never lecture without a black/whiteboard or huge-sheet-of-paper-and-coloured-pens available to me (yes, some universities still have blackboards - and I never remember to take chalk so have to scrounge some or rely upon what's left behind in the lecture theatre), as I need to interact with the class, pick up on what they don't understand, and interactively develop additional material on the board to clarify what we're talking about.
When I'm teaching flying, any brief starts with discussion with the student, as I need to start from what they know already, and that's a very variable feast. I also need to make sure that they *do* understand the key points before we fly - and using a standard form of presentation is seldom matched to that well.
Perhaps an instructor test is an oddball in that regard, as invariably the examiner knows as much as, or more than the "instructor". So, it really is about the delivery and knowledge, and the interaction will be of quite a different nature to a real lesson, where any misunderstanding on the part of the student isn't an act - it's real, and their rate of learning is seldom going to be as linear as with an FIE.
So, I'm not discounting PP as I'm a big user of it in some teaching environments. But, I still think that the 1:1 flight-briefing environment is a place where it should be used with a lot of caution, and NEVER in a linear "this is the order we're talking about it and will not vary" fashion.
G