Hello again.
I bought a ArgoFet 200-3 and I’m now going to reply to my own post with the measurements for any future reference.
First: On the bottom of the device there is a schematic indicating that all ports can be pulling 200A irrespectively of each other. This schematic leads me to believe I can load the device with a maximum of 600A
I did some tests with running winches and bow prop. See results below:
Load: 0A. Single: 0.02V Shared (3): 0.02V
Load: 65A. Single: 0.07V. Shared (3): 0.03V
Load: 100A Single: 0.10V Shared (3): 0.03V
Load: 165A. Single: 0.17 V Shared (3): 0.05V
Load: 355A. Shared (3): 0.12V
What I take away from this is that the outputs are separate and if you want to use the device as a single one way diode for use with only one output and optimize for maximum load and minimal voltage drop you should buy the ArgoFet 200-3 rather than 200-2 - the load is divided between the outputs as any parallel load and dividing a high load over multiple outputs is beneficiary and results in a lower voltage drop.
During my tests I ran the loads for 10 seconds (repeatedly) and could not tell that the ArgoFet became warm at all.
Here’s a video of one test made, the 355A on 3 outputs: https://youtu.be/FJyiFQYscZs?si=6edwQjrU4fkBPdPk