I don’t have the skills needed to break that down as you hope, but the 300w TDP and flops (single and otherwise) are identical to claimed on Vega64… in other words there isn’t better power efficiency defined in the envelop of the instinct.
Also the reason it runs so hot is because AMD is pushing the voltages high to try get more clockspeeds, thus performance. To launch your flagship watercooled card and have it give worse performance than its competitors flagship gaming gtx1080ti (which has been on the market almost 6 months already, so is halfway to seeing its replacement) is not what AMD would have hoped. Its still a better card for some applications, and price depending (its still moving too much and far above the target MSRP) for gaming, but it explains why AMD engineers would squeeze all the performance they can instead of chasing power numbers.
Also 1.3x the performance of the tesla is claimed, for 1.2x the power draw, so its actually actually still a net win as it is, I’m sure you could improve the performance per watt further with a mild down-clock though, I just don’t know how many applications where the lower performance per dollar investment AND per rack space is going to justify that but not be willing to change the factory settings themselves (AMD themselves may even have different bios’s depending on your application).