Some specific examples of real deadlines I'm thinking of include: Giving a talk at a conference, submitting a bid for a contract, anything involving the court system (continuances are by no means guaranteed), a product launch with a firm already publicized date, or even worse, a product launch with a firm already publicized date and dozens of external partners (this is what I do at work).

In most of these cases you can't really scale back; you're either ready by the deadline or you're not, with catastrophic consequences for not being ready.