"Hey, FuzzyDulop, we're a day before deadline but I've been thinking, we could do SUPER BRILLIANT IDEA THAT CHANGES EVERYTHING and it'd be amazing! What do you think?"
...
"You can forget about your deadline if you want that in, boss."
* skip forward a week *
"Hey, FuzzyDunlop, we're a day before deadline but..."
Dealt with this from an asshat running a semester-long school project. Solution: Drafting my own spec doc, sharing w/ rest of team, asking for comments, saying it would lock in two weeks.
Followed that doc for the next month or two.
Of course, the asshat was ticked off when the semester was about to close and tried to edit the doc (for the first time). I just said no.
I consider it a success even though even Those Kids who contribute nothing got As and I got a B+ despite working quite a bit.
And then getting chewed out for missing the original deadline. Usually from the boss who just drop the SUPER BRILLIANT IDEA THAT CHANGES EVERYTHING in your lab.
We get the sort of unsure, passive aggressive criticism, full of ifs and maybes. The sort that actually makes you feel worse because the boss appears to be personally disappointed.
Get chewed out proper and at least you know it's just because jobs have to be done.
...
"You can forget about your deadline if you want that in, boss."
* skip forward a week *
"Hey, FuzzyDunlop, we're a day before deadline but..."