The script girl/boy is in charge of continuity. Continuity in film is important because scenes, coverage, and inserts are often shot out of sequence. Keeping track of the continuity of plot, character development, blocking, wardrobe, hair and makeup is indeed chaotic, especially on a big production (on a small 5-day student film, not so much.)
Now keeping in mind the importance of continuity, it is only a small part to making a good film. It needs to be there, understood, but it should remain under the director’s radar. As should the script boy, who is definitely low on the filmmaking food chain. But what happens when the script boy gets an ego? What happens when the director becomes seduced by said script boy and lets the whole scene revolve around continuity?
One such example:
A simple scene really: A car parks on a residential street. A girl and boy get out of a car. The girl and boy see an old friend across the street, and proceed to cross the street. How could you get that wrong? It sounds so simple. Not for the student film crew. Here’s where the difficulty came bubbling to the surface. During blocking, the script boy pointed out that before crossing the street the girl is on the right, the boy on the left, but after crossing the street the girl is on the left and the boy is on the right. Continuity has run amuck.
The dubious “on-screen cross-over”. Somewhere, somehow, the girl (that would be me) has to cross-over the path of the boy to end up on the left side of the boy, thus preserving continuity. All this in one take. Natural.