What's wrong with "return on investment"? And what is a "term of art" exactly? I agree with Kerry and Pine both about the frustrations, but I also agree with Asaf in terms of all the improvements WMF has made. The problem with making a yearly chapter plan is the lack of knowledge on what "impact" (still better than any other word) was achieved the previous year, making estimation nearly impossible. For the Dutch chapter, the various projects (WLM etc) have been able to come up with their own measurements over time. The problem with any new project is that there is never anything to base estimates on. I am a terrible estimator myself (even when I have pretty good data to base my estimate on), but I enjoy finding creative ways to measure things. Right now we are in general terrible at measuring project-related chapter stuff, and the stuff we are good at measuring is hard to share with the people who need it most (see Asaf's comments about active editors).
Last night I had a long skype-chat with my gendergap friends in NL and we were plotting what we can measure now as a way of being able to measure impact after some (soon-to-be-dreamed-up) international women's day editing event in March. One of the problems with measuring edits is the need for anonymity that Asaf and Kerry talk about. So we need to somehow capture aggregated measurements, but how can we do this and how do we define a "gendergap-related edit"? Theoretically this is an edit made either by a new or existing editor -or- about a woman, and either one is prompted not by something random (organic growth model of Wikimedia projects such as Wikipedia), but specifically by something in our gendergap workgroup "output" (whatever that is). The return on investment (=what we get for giving our personal time) is the increase in such edits over time. At the end of the day, we need to measure "our" increase of aggregated edits against the "normal" increase in aggregated edits, and if we can never measure this, why don't we all just shut up and go back to editing? Well I believe that these efforts will at some point become measurable and I have good faith that these efforts are not just "drops in the bucket". Sometimes it helps to just keep trying to reinvent the wheel, and until we do, we keep at least a list of new and improved articles that we are sure were prompted by our efforts (though these are certainly not 100% of all the edits we have inspired).