It is important to genuinely learn the material, although question banks help towards the end.
But mind your high ground Mr LEVC, at-least two people contributing to this thread did degrees in Aeronautical Engineering before they ever went near the CPL, one of them a PhD in it as well. How much knowledge do you want to add up?
And being a good pilot starts with the first lesson of your PPL, via what you do with your flying before the CPL, then carries on after that....
G