Using RxDart Observable to merge streams as one for form submission
Concept of Single-Subscription Stream and Broadcast Stream
Intro to BehaviorSubject to replace StreamController.broadcast for additional function to go back in time to retrieve the latest stream values for form submission
Best practice on adding dispose function in Bloc class for the ability to close streams (or IDE might complain with warning)
Best practice on setting StreamController as private instance method to avoid confusion from newcomers working on the same project