[lgsilver]

I really agree with this advice. I would add that during those quiet conversations the best leads usually say, "we can make this deadline, but we'll need to do x/y/z", where x is increasing resources by a %, y is decreasing scope by some feature(s), and z is increasing time alotted by some days.

That constructive feedback is actionable and adds value. If your manager (or the business) chooses to ignore it, don't be frustrated, but when it's constructive, finite and actionable, you'll be surprised how often they'll make the changes.