I remember in the olden days, as a low ranked yudansha, becoming quite excited every time we were shown a new weapons pair form. We videoed it, usually from multiple angles, for future reference, and practiced until it was duly memorised.
Nowadays I might teach one or two new pair forms a week.
I never video them, nor expect the students to memorise them, (unless it is going to become part of their grading curriculum).
Instead of the butterfly collecting of the past, I just observe them fly by in the wild.
Kai Cho
Butterfly courtesy of Tanwyn Eacott Sensei