PK 4, beware the 'Americanism' of using 'a leading killer', - one of many causes, in the context of 'the leading cause', i.e. top of the list. The report does not support the view that this illusion(SD) is top of the list. The discussion relates to a model, computer simulation, as an aid to investigation. Take care not to over rate the problem of SD in commercial aviation.
However, it does warrant attention, but it may be more beneficial to focus on real aircraft demonstration vs forum discussion and false claims of training simulators.