GREAT explanations miti and hello. Thank you guys.
Miti, your explanation of the ground thing makes perfect sense. I needed that. And you're right, everything DC ends at the battery.
Now for a couple of minor clarifications Hello:
On a megayacht like the Smacktanic, one really could argue that just having the GFI and ONE main breaker for the two AC outlets, would be more than sufficient. I mean, if the breaker blows and you've only got two outlets, you can certainly figure out what to unplug, right?
Actually, I tell the ladies it's a "Maxi". I don't let on that I'm comparing it to an Opti - but hey, it's the whole E=MC+2 kind of thing (Einstein was a BFSailor you know).
Anyway, my whole design is built around the amp hours required to blast Barry White's "It's Ecstasy When You Lay Down Next to Me" at 103 decibels for 2 hours after sunset in the marina. I guess you're right about the 30 amp breaker.
As for the advanced troubleshooting on a tripped breaker in my design...you flatter me.
Seriously, at the end of the day, I'm sure there are a million reasons to spend a buttload of cash on the "best" possible set up. But, honestly, all I care about it what works at a basic level and what teaches me something in the process. And KISS works great at this point. I'm easily distracted.
You guys rock.
(PS - The USCG are obviously scared to death of Lake Travis. I've never seen them once. Lake Travis and Cape Horn - the two places in the world you'll never see the CG.)