The article in the OP doesn't conceder system efficiencies which are generally around 77%. But he may get away with it because the author either has the world's most inefficient refrigerator or he's just using the plate max current draw on the refrigerator's plate instead of actually using the watt meter he suggested in the article.
When considering how much electricity something uses think in watts, not amps. Watts are the true measure of electricity used, not amps.
I was a little unsure when reading the article if the appliances were using 12 amps at 120V (1440 watts) from the inverter or 12 amps at the roughly 70 volts from the panels (840 watts) or 12v from the 12v battery (144 watts). Amps and volts can vary but a Watt is a finite measurement of electricty.
If you think about electricity as water in a pipe then Watts would be the water, the actual volume or water (electricity) you are moving. Volts would be the water pressure in the pipe (or wire) and Amps would be how large the pipe is. Watts are the actual measure of energy used.
Volts X Amps = Watts
Watts / Volts = Amps
Watts / Amps = Volts