In this week's New Yorker, Tina Fey recounts nine "Lessons from Late Night" - what she learned from working with Lorne Michaels.
Lesson #7 is "Never cut to a closed door." Tina writes:
Lorne said this once in exasperation...the director had cut to a door a moment too soon, before the actor entered, and in that moment Lorne felt we had "lost the audience"...Lorne would have preferred that the camera cut follow the sound of the actor knocking on the door. Which is to say that the sketch should lead the cutting pattern, which is to say that content should dictate style.
From the Green Room: Let your message and your content dictate your speaking style. Most delivery problems stem from a lack of clarity about the content. If you are 100 percent clear on what you are trying to say, your delivery will flow much more naturally and the your audience will stay engaged.