Hi,
Second constructor call for mediator is caused by reflection mechanism. As you've probably noticed in mediator constructor there is ( and should be ) as less code as possible - main mediator initialization should be done in onRegister() method. You should not be worry of second constructor run - reflection mechanism creates only local variable so it is deleted as soon as all reflection info about mediator instance is gathered. This explanation is only for mediator - I don't know how you managed to have second viewComponent instance created. Can you send me some code? Or maybe put some example in fabrication google code issues section?
Thanks.
Rafał