Specifications are important, but it's funny how you arrive at them and what defining them over time reveals even if it's obvious on its face. When I was doing

Specifications are important, but it's funny how you arrive at them and what defining them over time reveals even if it's obvious on its face. When I was doing work on default player mass on Planimeter Game Engine 2D, we would reference the average male weight to serve as the specification for player characters' mass so we would have some reasonable metric defined for physics calculations. The team also did work on the Quake family of engines and so from time to time we would reference Source, and QuakeWorld. It turned out that between the time that Valve's Source Engine had been written and the time that Planimeter Game Engine 2D was written, the average male weight had went up by a fair amount, because they too used an average male weight for the default player mass for their physics calculations as well.