I just shared this very thought with one of my students this week; who tends to sandbag on me.This reminds me of something that I heard in the past in regard to practicing a technique incorrectly. Practice Long, Practice Wrong.
It was a reminder for the students to remember that if we are spending long hours practicing a technique incorrectly then all we are just doing is practicing wrong. Martial arts is hard enough. The last thing I want to do is spend 50+ hours practicing something the wrong way and then spend another 50+ hours correcting it.