Screen Writing - Entering and Exiting

In a screen plat, it's very rare that we're actually evennto see an entrance or an exit. That's because the main tool we have in screen writing is the cut. In fact, this is how farces are built, right? This is why a farce has so many different doors, so that we can watch those characters go in and out to the unified place. Each opportunity where somebody leaves or comes a leads to an opportunity for mistaken identity, humor, jokes, et cetera.