One thing I've learned from #SystemsThinking so far is that systems tend to be extremely robust and able to absorb a wide range of variation in their parameters. In some ways that's pretty depressing because that's why it's so hard to make systemic change.
The silver lining is that you can actually be moving a lot of parameters in the right direction and it won't seem like it's having any effect, but then it will flip to a new state seemingly overnight.