This is the problem with all the marketing BS. When I talked about “top clocks”, I wasn’t referring about “boost” clocks. I’m talking of the clocks that the SoC is designed for (that won’t appear on the box), i.e. a lot of laptops are not leaving “performance gaps” due to bad cooling, those SoCs are designed for that level of performance and attaching a fat copper heatsink won’t do much difference.
I had a lot of trouble with a client that complained that our board was not properly designed because the performance they were seeing was not “as advertised”. In the end we had to ship the whole thing to AMD, and have them test the system with a thermal sink. Everything was as expected.
If anyone is interested in this kind of stuff, your explanation is really good, so I won’t add anything because I’d probably do a terrible job :)