In Jet Li's version of "Taiji Zhang Sanfeng", how did Zhang Sanfeng achieve that grass turning into a ball in his hand when he practiced Taijiquan? Stunt or real?

Dizzy! If it's not a stunt, if it's real, then do we still need to develop weaponry! Tai Chi has a very strong technical meaning, listening to the power, Yang family old-timers will be able to put a bird in the hands and the bird can not fly off, but that's all, as for the air power is limited to the legend, Jet Li's this action than the legend of the degree of much higher.