The drills, techniques and exercises in these videos are not for one-time use. I've collected and used everything here throughout my volleyball career, as both a player and coach, and I know they improve setters.
Even while training for the 2000 Olympics, we repeated drills just like these over and over - there's no point in which you perfect them and get to stop. As any professional athlete will tell you, it's the constant repetition that makes you better, even if "better" is small, incremental improvements.
Coaches - while these are specifically for setters, I recommend spending time training every position player with these drills, specifically Wall Setting and Triangle Setting. As you know, everybody has to know how to set an out-of-system ball.
Setters - pay special attention to the Wall Setting videos. Your hand shape, position on the ball and setting motion are critical.
I recommend these drills at every practice. Contact me if you have questions about frequency of drills, or need thoughts on how to practice the multi-player drills with just one setter (coaches), or by yourself (players).