There needs to be a balance between the two. Neither extreme is good. We certainly don't need to be able to build the plane, but Mike is right, understanding how the systems interact/work together is critical to safely operate the Bus. Too little systems knowledge is even worse than too much, in my opinion.
As for training, soon we will go to the 9 month CQT cycles, so that will help in two ways -- fewer events to cover in each event and greater proficiency going into the events (less time to get rusty between events).
Lets just hope we keep our structure (training and standards combined and run by pilots) intact.