I think some of you are over-generalizing about weather minimums part 61 vs. part 141. It has nothing to do with which part of the FARs your training is conducted. Those weather minimums are dictated by insurance companies and what the school is willing to pay for with regards to insurance. The way the insurance company looks at it, the larger the school the larger the risk for someone to do something stupid. One way to minimize that risk is to place weather minimums on students.

That being said, when I was instructing (whether it was at the part 61 or the university part 141 school i taught at), if a student was a private pilot working on a commercial cross-country I really left the decision making up to them. Unless they are a total numbnut wanting to fly the mighty Warrior into freezing rain or something I say let 'em have at it. The FAA says they're good enough. A good instructor in that situation will tell a student what they think but they won't make the decision for the student. Scaring yourself and spending a night on an FBO couch because you got stuck with weather is one of the best ways to learn a lesson. Especially when you call your instructor and he tells you "Hate to say it but I told you so...guess I'll see you when you get back in the morning" Naaahhh, I wasn't that mean but I did bill my student for my time to drive down and get him and drive him back.