They want to expand that value into engineering and so are looking for something they can measure. I haven't seen anyone answer what can be measured to make a useful improvement though. I have a good "feeling" that some people I work with are better than others, but most are not so bad that we should fire them - but I don't know how to put that into something objective.
Most models of productivity look like factories with inputs, outputs, and processes. This is just not how engineering or craftsmanship happen.