But there clearly is a body of knowledge which you can discover yourself: you can interview candidates, read discussions on SO, read library code, and you will find some techniques are commonly used, and some are rarely used.
That distribution of what's known is changing over time regardless of what we do, because our peers are constantly learning and studying at different rates.
This feature has been around for years, and is so rarely used that only language mavens know about it. Thus, you can observe that this is a failed feature and avoid using it.
We can always reevaluate if people understand it later on, since that could change.
In a way I find your comment contradictory: on the one hand, you appreciate and embrace that the body of common knowledge can change. On the other hand, you use the current state of common knowledge as an argument against doing things that can improve the common knowledge.