Slim, Derek is basically right.
Told to me by an airline personnel manager - you are interviewed by pilots, sim checked by pilots. pilots hate groundschool. By far the most important thing is the flight tests and then sim rides. Groundschool must be passed, and obviously given two otherwise equal candidates first-time passes must be an advantage, but they mean little beyond that.
I am an ATPL ground instructor, and still i have to see his point!