What are we Optimizing?
When we optimize for GNOME the first thing to remember is this: we are not trying to make the program better, we are trying to make the person using the computer happier.
Better programs make people happier, but there are some improvements that will make them a lot happier than others: Responsiveness, start-up time, easy to access commands and not having the computer go into swap the moment more than two programs are open.
Traditional optimization tackles concepts like CPU use, code size, the number of mouse clicks and the memory use of the program. This second list has been chosen to correlate with the first list, however there is an important difference: The person using GNOME doesn't care about the second list, but they care a lot about the first list. When optimizing GNOME programs we will reduce CPU use, memory use and all those things, but these are the means to the end, not the final goal. We are optimizing for people.