I fully agree with this with the caveat that you need to both join them in the exercises (lead by example) and observe them while they do the exercises so that you can see what they're doing and give appropriate correction.Do with them. Don't just stand around describing techniques or counting off kicks for them to do while you watch.
Students need to see things done correctly, many times. They need to see in the instructor that hapkido is a lifetime fitness commitment and not just a climb to black belt where you rest on laurels.
Class time is not my personal training time. I do daily practice and focus on improving my own skills during that time. I make sure to participate in the drills enough to allow the students to see the technique performed correctly, but I also spend a good amount of time observing what my students are doing.