Presenter view is a superb tool for any trainer. You can have aide memoir notes which the instructor can read on their laptop but the delegates can't see, you can skip slides that might be irrelevant without delegates being any the wiser, you can 'hide' slides that might be relevant for some audiences but not others and activate them at the flick of a mouse. You can view on your laptop the next slides that are in sequence, as well as the hidden ones you may wish to activate. You can start/stop video or sound from your laptop without dragging a mouse across the main presentation for all to see.
Or of course you can rely on pure and total memory for 3 Days without reference to any research, read every bullet point on your own presentation to jog your memory about what you've got to talk about and hope you don't forget anything, and knowing you are going through every single slide on your presentation (whether the delegates like it or not) then by all means don't use it.
To suggest that trainers don't know what they are talking about because they use an extremely effective piece of software is frankly insulting (and beneath you based on previous posts).
Regards
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Edited now I've calmed down
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