Recently I've come across one article which I think you can find interesting. Someone may take a steaming dump all over it, but it clarified some of my questions.
https://yandex.ru/collections/card/5bd6 ... 0062a8d80/
https://yandex.ru/collections/card/5bce ... 0bfbe9324/
https://yandex.ru/collections/card/5bd4 ... 084479e62/
https://yandex.ru/collections/card/5bd5 ... 00e2a8364/
https://yandex.ru/collections/card/5bd2 ... 0b516ff02/