Understanding the functions
Zenkutsu-dachi supports many forward movements; kokutsu-dachi organizes more support at the rear; kiba-dachi offers a side frame. Fudo-dachi, frequently associated with Sochin, aims for a stable structure that can remain mobile. Neko-ashi-dachi makes the front foot relatively available. Kosa-dachi crosses the supports in certain sequences. The weight percentages sometimes taught are method benchmarks, not constants for each body and each moment.
The passage counts as much as the arrival
Observe the transition: direction of gaze, path of the feet and ability to continue after the action. A very low position that prevents the next step does not serve the same purpose as a controlled study posture. The knee and foot must accompany the direction of the action. An amplitude that hinders execution deserves adaptation with the teacher rather than forced imitation.
Locate an available balance
After a position, ask yourself if you can go back in the planned direction without additional movement intended to catch up. Also observe the distribution of support, the direction of the pelvis and the orientation of the gaze. A width that is comfortable for one practitioner may bother another. The basic positions provide a framework for study; their dimensions are adjusted with the teacher. Maintaining a still posture for a very long time does not guarantee that the transition will be correct. The ability to receive information and follow through is as important as the feeling of stability.
Compare the sides with a precise criterion
Make the same pass to the right then to the left, at a speed that allows observation. Choose a single criterion: path of the foot, height of the center or direction of the knee. A video taken from the front provides information on the width; a side view shows other details. No single angle describes the entire movement. Note the difference and prepare a question for class. Trying to immediately obtain two perfectly identical sides can mask the causes of the imbalance; understanding the transition allows for a more lasting correction.