It's not really that much about secrecy. Most of the tools are free or open source (with the exception of audio tools which can be for the most part substituted with eac3to).
The problem is that the "body of knowledge" is rather extensive if you want to cover all the corner cases and imaginative ways in which authoring houses screw things up. To be able to filter the video correctly you need to know a bit how the h264 codec works, learn your color formats, color spaces, a little signal processing, a few tables from ITU-R recommendations and some proficiency in RPN wouldn't hurt. As such it is difficult to put it all down in one guide. To make it worse, as with every niche community there are disagreements and transient "fashions". At the end of the day though this is very much chasing rapidly diminishing returns.
Just trying to point out that a great way to learn more would be to review exactly how each release was put together. Even without the "why" this would be a useful learning opportunity.
The problem is that the "body of knowledge" is rather extensive if you want to cover all the corner cases and imaginative ways in which authoring houses screw things up. To be able to filter the video correctly you need to know a bit how the h264 codec works, learn your color formats, color spaces, a little signal processing, a few tables from ITU-R recommendations and some proficiency in RPN wouldn't hurt. As such it is difficult to put it all down in one guide. To make it worse, as with every niche community there are disagreements and transient "fashions". At the end of the day though this is very much chasing rapidly diminishing returns.