All deadline-based management does is turn the code to mush, so that tasks in 3 years time from now take twice as long as they would have, with even less delive

All deadline-based management does is turn the code to mush, so that tasks in 3 years time from now take twice as long as they would have, with even less delivery predicability (which of course they'll respond to by imposing deadlines more aggressively, and so on goes the downward spiral). It's a marathon, not a sprint.