The reason I am here and have been since college is a simple reason: No one taught me how to do this.
Someone
did teach me how to do this.
Not just one person, really- most of what I have learned about stage management has come directly from working with or talking to other stage managers. I did an apprenticeship, assisting one SM for the season- most of the way that I stage manage is because of what she taught me. She gave me the benefit of her knowledge and experience without hesitation, and I want to do the same for someone else.
I also agree with what's been said about competition already on this topic- I have to feel confident enough in myself that I have the tools and ability to do this job, and I can't worry about anyone else. There are several other stage managers on this site that work at about the same level that I do, and in the same geographical area, and who (I'm sure) compete with me for jobs. I am betting that when I post on the forum, those are not the people who are using my advice. (If they are, great.) But I'm betting that most of the people are younger and less experienced than I am, and I think the only thing that is going to make us competitors is experience.
I think that a great stage manager is the result of among other things, their ability to work with people, time management, technical ability, and mostly, their experience. Most stage managers at the same level as you are probably good at the first three. The only thing separating you from them is your experience, and how you use that experience to inform your work. (You said something similar to me once, Matthew). If I have experience in opera, is telling someone else about that experience going to be the same as them working on an opera? No- it may
help them in that experience, and frankly I'm ok with that. It may raise the industry standard - and I'm ok with that too.
I do understand where your friend is coming from- it's a hard field to make a living in, in the first place. And if they don't want to share what they know, I don't blame them. I also think that to be really active in this forum can take up a lot of time- and not everyone wants to go home at the end of the day and think about stage management some more. Having a "real life" for some people means putting away the job completely when not at work.