I usually do not comment on how fellow practitioner doing in their videos'. but I usually just add some more info in general.
1. short strike or short fist set is focusing on using your forearm to temporarily restrain or deflect the opponent's forearm. we then strike almost at the same.
time. it is close or short distance infighting.
2. use of the whole body to generate short burst of power and the angle of your strike are both important. most of the time, you are hitting the soft spots, such as ribside, chin, sternum, heart etc. we do not need to use a lot of power.
3. the practice set would be a good fit for other mantis sets/routines, incidentally, liu he does not have a lot of forms/routines.
b/c you are practicing a lot of skills of using your forearm to intercept--
4. actually, some of them are throws and not just hits as shown in the first video.
cool, thanks for posting.