So now the requirement is not just to run a micro benchmark, but to run one with inputs that approximate the distribution of production inputs, along all possib

So now the requirement is not just to run a micro benchmark, but to run one with inputs that approximate the distribution of production inputs, along all possible axes. For many sorts of projects, this is totally unreasonable. It's easy to figure out how the code performs with a given input, it is much harder to figure out what the inputs really are like. In this particular case I'd expect the change to be motivated by profiling of the real production instances. And that makes it pretty obvious how the change should be evaluated. "We're spending more time than is reasonable in linear scans, so the worst case inputs must be worse than expected. Switch to a data structure more suited to large inputs, and see if CPU use improves in the next rollout."