Mike P. said:
What time of year did your friends do the trip before? Weather will be a key, does everyone have same drive? Have you hiked with this groups in bad weather before? Does everyone have same idea of what is bad winter weather? If I said define this weather as good bad, fair, average or poor: 25 degrees, 150 feet visibility, snow showers & 40 MPH, you'd get a lot of different answers. Does everyone in your group feel the same way? What does 50 or 60 MPH wind do to your answer?
This is an excellent question and observation.
IME, these sorts of scenarios are not only commonplace but the source of the most team friction (and open conflict) and poor safety decisions. This gets worse when you mix in personal ambitions, drives, fears and insecurities. Things get really bad really fast. I've seen groups split in the face of a gale over these things, a situation that should be avoided.
Problem is, I have no good advice on how to figure this out ahead of time. How does everybody get on the same page about how they are going to agree to make decisions when it hits the fan?
One possible solution is to establish several go/no-go points along the way where you all commit ahead of time to re-evaluate the decisions. Some that seem to be obvious places for this include: Mad hut, Thunderstorm Junction, Edmonds Col (retreat via perch/randolph path), junction with Jewell, Washingon (retreat via lion head), junction Ammonusuc Ravine.
IMO, the Edmunds Col decision point may be the most critical. There aren't any really good retreat options between Edmunds and the Washington Summit. I would consider that to be a real point of no return, so to speak.
Might be really good to decide on a decision rule ahead of time. Majority vote often leads to hard feelings. Veto power to all for retreat is safer but the will piss of the ambitious. Choosing a trip leader with final say is yet another option.