We must focus on the aspects of karate, which are within our grasp. We would all love to do intense scenario training all of the time, but this is not feasible nor safe. Sometimes we don't have access to a training partner or even a heavy bag. This doesn't mean we stop practicing karate. It means we focus on what we can. We practice kata, we analyze the movements and hypothesize efficient application, we test our bodies and our spirit through vigorous exercise. We focus on what we can. When we do have access to these things, we will have a foundation to work from and it will be easier to learn new concepts. You don't need a partner to practice efficient movement, you don't need scenario training to practice efficient movement, you don't need a heavy bag to practice efficient movement.