Which made me think, why couldn't there be some kind of warning built into the Garmin software on my ipad(or CP) that would warn of approaching an obvious charted hazard?

I always run with the track recording on the Bluechart. I use the tool for visual reference while underway as well as a record of our course for later review(very interesting data to have-also alarming in this particular case). So it would seem quite simple to add a forward looking software, that would say, "hello,...do you see what I see ahead?" Easy stuff!

What you say is exactly right-brain disconnect- is the biggest hazard out there on my boat. It's not my tools-they are brilliant today. Why does the disconnect happen? In my case, I was distracted by how engrossed I was in sailing a particular stretch of water(there are many potential distractions in my world). And I was 'racing' with another boat, and engrossed in taking photos. Add to this mix, I'm the sole navigator(by my choice). Result: Total navigational failure on my part.

It's quite a story that I'll share once things get too boring here this fall/winter. What saved me? 12.9 feet of tidal range. Back in the old days, this could easily happen, and you were never aware of it. Today, it's recorded on your screen.