Sooo, nevermind.
Longer version: I researched the topic once again as overloading stuff from std namespace seemed strange and I found out, that doing so is indeed sometimes used, but not recommended (like, really NOT RECOMMENDED) by the standard. TBH such code should be considered ill-formed and misdesigned. Oh, and in case of boost.geometry it was actually custom get function in a different namespace which was then inlined (that's how you call using namespace stuff;?) hence my image of said situation was wrong.
Man, killing off (is that even a correct collocation?) my own proposal feels bad.
Sorry for the fuss, I should have looked into it thoroughly.