In the last couple of posts, I've discussed how I've been refining my body mechanics by keeping energy at the crown of the head (i.e. not slouching) and how this has led to getting a feel for energy in the center of the hips.
As I continued working on developing this feeling, I eventually realized that it dramatically changed how I stand on one leg. Having the forces aligned from the center of the foot, through the hip, and projecting out of the crown made the posture considerably more comfortable - I'm not completely certain why the posture became more comfortable but previous to this, when I would bend my knee while on one leg, it would quickly start to feel uncomfortable. With the proper alignment, I can now bend my knee much further than before with no discomfort and I eventually get to the point where I feel like I'm balanced on the bones and tendons.
This change has made a substantial difference in my Taiji form during transitions. For example, when doing single whip, the first part of the posture is to sink into the rear foot while pivoting on the front foot. This transition has always given me a lot of problems, particularly with the knee of the rear leg. Now, as I sink onto the rear leg, I focus on getting that same feeling that I have while on one leg and that gets me on the back leg without discomfort and prevents me from torquing my knee while I pivot (which means I need to twist my waist and upper body a lot more than before).
Once the pivot is done, the second part of the posture is to sink completely onto the (formerly) front leg and lift the (formerly) rear leg to transition into a bow stance. I've always found this transition to be tricky also - in part because of discomfort in the knee and in part due to trying to keep balance during the transition into the bow stance - but keeping the alignment/energy while sinking onto the (formerly) front leg makes the transition more comfortable and, since standing on the leg is now more stable, finishing the transition to the bow stance is also more stable.
These changes have made my legs a lot more active while shifting weight - bending and straightening much more than previously - and this has improved things all over the Slow form and in the ILC 15 Basic Exercises.