...and suggesting that IF the guy was running to a route he'd plotted thru there, and IF he was relying on his AP at the time, and IF the tide had begun to ebb by that time, and IF he was having to reset his AP after dodging lobster pots, or whatever, that "No Drift" feature of the Simrad/B&G pilot would have been nice to have, and given him a better chance than the Raymarine of staying closer to his intended track... IF he was paying attention, of course...

Hey, I'm just grasping at straws, I suppose, in an effort to come up with potential or likely contributing factors... Seems that's all one is left to do, in an effort to explain how a professional captain drives a $2.4 million 70-footer with 3 chartplotter screens in the cockpit into a known/charted obstruction on a perfect summer afternoon... (grin)

I still think, however, your scenario is the most likely, and the CG investigation is unlikely to determine a cause much more specific than that the guy simply screwed up, and lost his situational awareness of the yacht's position...