While working at IBM I was charged with improving the performance of a product that included several web applications, all of which were developed and designed by separate teams.
The designs for the applications were created by a variety of graphic and interaction designers, most of whom where not familiar with the details of web performance.
Without centralized control of the teams, I needed a way to unify them behind a performance goal, and help them identify the the major areas that needed improvement.
The way I went about unifying the teams behind a goal was to publish "the performance formula" to each of them.
This formula showed how our application would perform on the type of network that we were targeting. I also called out particular aspects of the formula in plain language so that the goal was as tractable as possible to both technical and non-technical people.
This formula helped unite all of the teams behind a goal, while allowing each team to determine how best to improve their particular application. The plain language helped communicate the impact of certain design decisions (e.g. heavy background graphic use) to the graphic and interaction designers.