[dragonwriter]

And any decent engineering team will accept that a project has deadlines and raise progressively more serious risks with appropriate explanations up the chain as the confidence that completion will occur before the deadline declines below near-certainty.

Deadlines can be legitimate project requirements as much as functional requirements are. Identifying practical conflicts between requirements is part of what an engineering team does. Managing resolution of those once they are identified so that the customer gets the best result achievable is what a PM does.