>>mattjh+(OP)
One thing I think is missing is an understanding of why there is such a top-down push for timelines: because saying "we aren't sure when this feature will be delivered" makes sales people look like they don't know what they are talking about. Which.... well.
They would much rather confidently repeat a date that is totally unfounded rubbish which will have to be rolled back later, because then they can blame the engineering team for not delivering to their estimate.