1. Is the tech roller invulnerable during the roll animation? Or is he vulnerable at the end of the roll animation registering as a crouching non-defender? 2. I have done an elbow-knee knock down with Sarah. I did a b+K, d+K+G to sweep them. The victim tech rolls and the sweep passes harmlessly under them. Was I too slow or is there some invulnerability during the tech roll? I ask these questions due to my doubts over the practicality of using the TR, sidestep, P+G throw escape, G technique as listed in TRIAL 18A against a Leifei player going for the flying punch for the backstagger combo of death.