Exactly. There's a great Good Eats about it. For example, the recipe I used called for two gallons of liquid and one cup of salt. That's a pretty low concentration.

In the end, I don't care how it works, I just know it's friggin' delicious!

*edit*
To be clear, because it was just the breast, I halved the recipe I used. .5 gallons of water and .5 gallons of chicken broth.