Hi mineiro!
Maybe I don't understood your phrase.
That is. You don't understood phrase.
The problem with Neural Network is exactly that solution is beyond understanding.
The problem is not the process, is the solution.
In mathematical functions (exponential, factorial, polynomial ...) you solve the equations and you can isolate how each variable affect the result, not always easy but in principle always posible. That can help to find real mechanism behind input-ouput asociations.
In Neural Networks you solve input-outputs asociations and you don't know why that work!
Just some months ago Max Tegmark with Brian Keating:
https://www.youtube.com/watch?v=pFDqI3pKmec