GI Jane combat scene

This?



I assume because guns and bombs and **** were going off, and people getting shot and blown up. It increased the action and tension.

Perhaps the director or studio wanted to do that effect in the original cut of the movie but perhaps because of...
time or budget constraints;
missteps in the filming or editing process;
technical limitations;
hindsight into the filmmaking process were allowed to add the special effect into the DVD cut of the film.

Not all added scenes in special editions and director's cuts make a film better.

This bring's to mind Blade Runner Director's Cut.

I much preferred the original, the narrative gave it a film noir feel and really explained things.