I just did Told Dagor +3 and last boss i was kinda schocked. After 5-7 wipes players in my groups start asking about boss mechanics. I thought they just played badly at that moment but no. 3 players in my group were completly clueless what boss does. And when we finaly killed him. Those 3 players get achievement for heroic and mythic 0 Tol Dagor. So thank you very much Blizz that mythic+ is now infested with clueless players becouse they completly skipped dungeon progression thanks to free warfront gear.