I've been doing too much yardwork so my mind gets to wandering.
The fly fishing community is pretty gregarious and sharing - but, only up to a point. The general public get a dose of general information. Regular fishing buddies get the benefit of a lot more experience and learning.
However, is there some information that is too good to tell anyone. The information could be techniques, flies, or locations. I am not asking that the information be revealed, just whether there is something that gives a perceived edge and you want to keep it to yourself.
For me, techniques and flies can be common knowledge, unless I was given the information from someone else. If it came from a buddy, it is up to them for further distribution. I would be very picky about information on my local fishing spots. For me, the spots are somewhat predictable. If someone fished and removed my underwater pals, I would miss them.
Of course, the posts could get you in trouble with your close buddies.
Secrets?
Ants
PS. Robert Traver's book has a great photo of a fly fisherman hiding his tire tracks after turning onto a smaller road. The dirt road leads to a spot that seems to be too good to share.