The challenge of acting backward

I know that most films are shot out of chronological order, but it seems to me that this would have been shot exactly in reverse chronological order because of the evolution of Pacino's head and facial hair. There's really no way they could have afforded the time it would take the other way (considering when this was released in relationship to when the story actually happened, and for simple logistical reasons). So basically, Pacino had to act all of his blow-up and anxiety scenes and then draw that back in and finish the shoot as the the naive young rookie. Kind of interesting.