This also applies to programmer productivity statements i.e. the best programmers are 10x more productive than the worst. Productivity is extremely hard to measure. You can give small tests like in Mythical Man Month and there is no doubt there are better programmers. But the quantified amount is still a WAG.
you forgot that you won a prize too: <a href="http://twproject.blogspot.com/2007/03/teamwork-wins-2007-jolt-productivity.html" rel="nofollow">http://twproject.blogspot.com/2007/03/teamwork-wins-2007-jol...</a>