Well thought out response, that is my gut feeling as well. I think packaging could have a larger than expected effect too, especially CPUs with a thermal cap.

Well thought out response, that is my gut feeling as well. I think packaging could have a larger than expected effect too, especially CPUs with a thermal cap. This kind of in situ measurement might be useful to feed into a job scheduler's weight or something but at the end of the day "environment is different" and maybe you have to derate your cluster's expected performance to account?