It's a look at two expressions of the Form - for both balance and martial emphasis.
You can apply the same principles for any other purpose, rhythm, pace, coordination, breath, circularity etc

There is no right nor wrong in this exercise, for it is just an exercise. An opportunity for you to look into the components of the form and play with those that have more meaning for you.

If the martial element takes your fancy, then consider looking at the Complete Tai Chi Course as there is a component in each of the workshops that focuses on explaining in greater depth the applications for each of the postures covered.