The description states:
"Where in the graphical element, as a percentage from 0.0 to 1.0, Flex samples the associated color at 100%. For example, a ratio of 0.33 means Flex begins the transition to that color 33% of the way through the graphical element."
These two sentences seem to contradict. The first one is what I've seen in practice- if you set a ratio to .5, the transition to that color will be complete 50% through the graphical element. It does not begin the transition at that point like the "For example" states.