>>11036397Doesn't work for AY because of how he sculpts the knee joint. A lot of plastic is removed from the back of the knee to get as tight a bend as possible. The knee ring will have to be very thin which will lead to extra gaping at the front.
However it is a valid solution but seeing how Yamaguchi sculpts in Blender, he might not have the expertise to apply the fix. The knee ring has to to have varying thickness, more in the front, little in the back. You need to be very careful with the measurements of the thigh-knee-shin combo and this is something Blender can't do.
There's also the issues of tolerances as it can lead to paint rub and ruin the whole figure.