I have a similar method. Turn off the main breaker on the boat, turn off the inlet breaker near the power cord inlet, Turn off the dockside power breaker then remove the cord from the boat. As a point of interest, if I am leaving for any length of time say a weekend trip, I will be closing up the cord in a plastic bag to keep moisture from entering the terminals and causing corrosion. I have had an incident with a corroded plug dock side causing over heating and as of today ordered a smart plug for the boat end and the marina is going to charge me to replace THEIR dockside outlet. I had read everything MaineSail had written about them, it was on my list but unfortunately way at the bottom. Live and Learn, thankfully I was on the boat when the magic electron show began and was able to depower the system before anything really bad happened. Pictures to follow.