Sigh, let's go step by step.
Let's presume I'm maintaining a solid 55% winrate in some division (Silver IV). Sadly, I've lost my division advancement twice. Nonetheless, I hold my 55% winrate. My elo has risen (due to more wins than losses) much faster than my division. That may be fine for me, but it turns out that this is currently expected behavior. In fact, the average elo in my division (Silver IV) is no longer where it was when the system was devised (say around 1300 or so). Over time, the average elo increases, this is the definition of getting harder. It causes pooling in the lowest division (if the average elo in Silver IV is inflated to 1500 then 1200-1500 elo players will be pushed down into Silver V, making the variance and range of skill there dramatically different than the next tier. This behavior is likely not intended.
Simply put, a system that holds players in a division despite their maintaining an above average winrate has negative drag.