Whissper,
When i did AA in 2007 it was required that you had passed all your exams before any airlines could offer you a job. A good attendance record was also looked upon highly.
As for attitude, after spending 1 year at AA with the instructors they get to know the students fairly well and get to know how each student conducts themselves and how motivated and interested they really are.
The guys in my year that were sent there by their parents or clearly had no real interest in being there missed out on jobs. Most of the instructors are good guys but if you piss them off and make their job hard then you cant expect them to recommend to you for a job.