The biggest issue with control is that if we assume superintelligence a priori then it would be able to make the best decisions to evade detection, to avoid being caught, to even appear stupid enough that humans would not be very worried. I think it would be impossible to guarantee any kind of control given we don’t really know what intelligence even is. It is not impossible to imagine that it already exists as a substrate of the communication/financial/bureaucratic network we have created.
I find most interesting that we ignore that even the dumbest of super intelligences would start from having a very clear understanding of all the content on this section.
A selection method could be created based physical measurement of its net energy demands and therefore its sustainability as part of the broader ecosystem of intelligences. New intelligences should not be able to draw in energy density to intelligence density larger than that of biological counterparts. New intelligences should enter the ecosystem maintaining the stability of the existing network. The attractive feature of this approach is that presumably maintaining or even broadening the ecosystem network is consistent with what has evolutionarily been tested over several million years, so must be relatively robust. Lets call it SuperSustainableIntelligence?