I think being calm and let your body be in that calm state definately helps in creating changes. After all, this is the same for digestion. Digestion only works correctly if you are relaxed, because if your body is in 'fight or flight mode' , the body does not consider your digestion the priority at the moment, but your nervous system and muscles since they help you out of a stressing situatio. So when you eat and digest, you should also be very calm and such for optimal digestion.
So yeah, it would make sense that if you put pressure on your body you should always make sure you do not put so much stress on it that it comes in this same 'fight or flight'mode, since maybe that blocks any changes from happening. The body is then in defence mode too much, not in 'repair' mode. Maybe the best would be to, while facepulling, is to do something extremely relaxing. For example watch a comedy show or movie or whatever to make your mind positivive, put on relaxing music etc etc
At least, my 2 cents;)