They would have been better off if they were actually using their unlock FOB's, because they would have had more detail and information on that shoal. Inexplicably, according to the report, they were only using the world base chart, and did not unlock the detailed charts.
I have played with Expedition and it certainly takes many other chart formats besides CMap. I don't spend any time on SA, so don't know what the poster you refer to said. I suspect CMap may be considered "preferred" by some because free pirated copies of world-wide CMap charts are in wide circulation. However, this was not the case on Vestas - they paid for their CMap charts.
I started out thinking that the Vestas navigator just simply screwed up in a "normal" way - there but for the grace of God go I - sometimes bad things just happen - etc. Definitely gave him the benefit of the doubt.
Now I realize that this would never happen to me - I simply would not make this mistake in the way he did. Not in any circumstances, because I would never commit any of the basic navigational errors he did. Ever. That report was the most damning thing a navigator could ever experience.
I certainly may someday brick our boat for many stupid reasons, including bad navigation or even relying too much on our chartplotter and/or electronic charts - but never because I purposefully turned off all warning systems, refused to actually load any charts, and knowingly charted a route over clearly marked dangers without checking on them further.
Mark