dsimic: I've bought and checked with a better 5A cable. Now the voltage at the Type-C connector is 4.9V at max load, so the max PBP can draw from DC/Type-C VBUS is 11.34W (that's what I measured).
So that's the same as your theoretical 11.4W limit.
So that's the same as your theoretical 11.4W limit.
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