Yes and No.. 30amps should be two legs.. so he was drawing all that power through ONE leg. It should have definatly tripped the breaker before smoking the outlet
30A shore power is 120V Hot, Neutral, Ground. It is one 30A leg not two 15's... Many boats of this vintage were poorly wired, as AC and DC is concerned. Most all of these boats use a single 15A circuit breaker to power every outlet on the boat. This means the last outlet in the chain is depending on all the connections before it to work properly. I have seen as many as NINE outlets on one 15A breaker, all daisy chained...
The MAX I like to see on any 30A shore power cord is 80% or 24A but 70% or 21 amps is even safer. We also can't forget the loads of a water heater, 1200W - 1500W, a battery charger and any other AC sources that need to be added to your heater and iron.
Running an iron and a space heater on a 30A service is a recipe for burning down a marina and I have not even added and water heater, battery charger, microwave or coffee maker.
I see LOTS of stuff melted down by overloading a boats AC system. Breakers do not always trip at face value and any resistance in the terminations or circuit, like we get on boats, can heat a wire beyond the melting point before a breaker trips. This is how boat fires start!
If you want two 1500W devices add a second 30A service to the vessel with its own main breaker and branch circuit for more outlets.. Many do this to run air conditioning but you can install them for boats that winter and heat with electric too. The only other option is to manually shut everything else off before using a high draw item.
Drawing too much current is dangerous ESPECIALLY WITH OLD WIRING ON OLD BOATS!!!