Yes it is helpful to get you in the mindset of a 121 ground school. It is not nearly as in depth, nor as intensive but it will challenge you and give you a good idea of what airline training will be like. That's why eagle is using it for low time guys and girls. They invest a lot of money to train you and if you fail out it hurts the company. Even if you pass the ATP class, it doesn't guarantee you can pass ground school but it let's them know you have the aptitude and ability to (I.e. Minimal risk).