A lot of the "secrecy" has to do with 2 things:
Some, "pure lineages" are more concerned with dilution. The "unpure" ones are concerned with control.
This is paranoid, to say the least, and betrays a complete lack of understanding of the Vajrayana.
The OP said nothing about Vajrayana specifically, and neither did I. And there's nothing paranoid about it.
In the thread you linked
, the OP said:
Firts of all, I' like to say that I totally understand the reasons for keeping the teachings, practices, ect. secret from "outsiders", but what's bothering me a little bit lately is the secrecy within the circle of "insiders".
And I assert that the reason for this secrecy is to prevent dilution, and also confusion. If a pure lineage exists, the teachings are passed on to each student when they are ready to know, and in a skillful means by which they can understand them. A skillful teacher then can tell 20 students the same thing in 20 different ways, and still not dilute the original message. Confusion comes in when the students do not fully understand the teachings though, and begin to talk about them amongst each other, and eventually the entire set of teachings can lose its meaning. This is what I mean by dilution.
As for control:
There are quite a few Vajrayana teachers out there, who, on the one hand, are urging their disciples strongly to keep the secrecy and not to share their experiences even with fellow practitioners, but, on the other hand, are willing to share these secret Vajrayana methods with virtually everyone who's willing to pay for it. And by this way, even a fraud who's teaching completely useless practices is able to continuously gather more and more disciples who never ever going to realize that all they are doing is wasting their time. And even if chances might be low that the Vajrayana teacher you're following is a fraud, it's still well known that this is the way many bogus cult leaders manage to keep their disciples following them. And even if your Lama is actually really a complete fraud, chances are high that you'll never going to know this because within the tibetan "Lama community" even the real and honest teachers generally tend to keep silent about the "bad apples" among them.
This exemplifies the control aspect. The less you know, and the more your teacher appears to know, the more a dependency is fostered. And the more 'esteemed' that teacher becomes, usually through word of mouth from the followers (read followers, not students, for this is not a 'pure lineage', but a con), it only serves to bolster the ego of the 'teacher' in question, keep the followers enchanted, and fatten the pocketbooks for the 'teacher' on the receiving end.
One should hope, that in any tradition, or any walk of life for that matter, that when one accepts someone as a teacher, they receive one who is more concerned about dilution and confusion than about control.
The dharma is free. You can learn from the Buddha...
A small problem with this is the fact that the Buddha is dead, but anyway...
Eh, one can learn from the Buddha's teachings, and use them to realize the Buddha within, without the need for a living teacher.
Let's not forget that without the Buddha, there is no Buddhism. Thus, all of the various (real) branches of Buddhism are branches of the original tree of Shakyamuni Buddha. So if one cannot learn directly from the source (since he's dead), and one cannot learn from the teachings of the source (whether those teachings are from the sutras themselves or from living masters), then how do you suppose one will learn?
All I'm saying is that a teacher, or living master, is not necessary in order to achieve an Awakened state. It might be necessary in order to be a "Vajrayana Buddhist", or in order to adhere to any other of the many sets of teachings and practices perpetuated throughout history, but not necessary for Awakening.
...without any sort of formal sangha...
According to which tradition? In every tradition I now of one goes for refuge to the three jewels: Buddha, Dharma and Sangha.
Of course. If you view the sangha as a separate set of communities, lineages, and cliques, by all means. Then you have "sangha X, sangha Y, sangha Z, sangha ..." ad nauseum.
I don't view it that way. I recognize that there are individual lineages, and various teachings within them, and I'm perfectly okay with that. But I view the sangha on the global scale. I don't decide to pick 10 or 20, or 1,000 people out of the entire human populace, and call them "my sangha" so that I can feel better in my devotional choices.
It's one world, one human population, one sangha. Please note that I did say "formal sangha", which would infers a specific lineage or community.
Since you brought up Vajrayana, the Dalai Lama is quoted as saying, "I am a citizen of the world." Do you think that he views the sangha only as those around him who adhere to Vajrayana Buddhism? Certainly he sees it as a part of the sangha, but the entire ideal of the bodhisattva is to honor every sentient being, is it not? That being the case, such separations between this lineage and that lineage are only useful in a conventional sense.
...and then you have no vows to remain quiet about anything.
Unless you are practicing Vajrayana.
Again, the OP said nothing about Vajrayana, and neither did I.