Flexibility’s a tricky thing compared to the other components of fitness, because it often takes so long to see results. With weight training people usually can begin feeling stronger within a few weeks, looking better after two months. With cardio training results can be felt in as little as two weeks. But flexibility? It can take months of consistent training, and that can get discouraging. In my experience the genetic/biomechanical differences from individual to individual are much more obvious in this area than cardio or strength training.
I usually run students through a short sequence of hip openers in all my class levels. I’m not familiar with Yee’s video so he might do something similar or better. But here’s mine:
Runner’s lunge
Crescent
From Crescent: bend forward at the waist and move the arms to the inside of the lead leg. If the forearms can’t rest comfortably on the floor then rest them on props. From this position the stretch in the hip of the lead leg can be increased by rolling onto the outside edge of the lead foot.
From this last position straighten slowly into the lead knee, let the toes of the lead foot rise up. Keeping the knee straight bend forward at the waist into a modified Bound Angle Pose.
If your range of motion allows it you can begin to extend the straight lead leg further out, working towards Hanumanasana (splits). Again, props like blocks always help during the intermediary stages here.
Hope this helps.
Orion