Those who have been around taiji masters (or viewed videos on You Tube) are often amazed at seemingly impossible moves. An aura of mystique surrounds taiji/qigong. Some teachers play up to the mystique and have their followers in awe. At Master Jesse's summer training he insisted a number of times that there is nothing "magic" about taiji. Taiji is practice—long term gongfu.
Recently, I tried an experiment to see how my rooting and peng (ward off) postures are coming along. Leaving the university sports center I met one of the football coaches. (Big guy, much taller than me, at a guess 300+ pounds of solid linebacker.) We chatted for a while and I asked him if he would push me. (Bit foolish you might say!) I assumed a peng position, bow stance, asked him to push my wrist and elbow, slowly adding more pressure. I relaxed (song) into my structure. After a while I asked him to stop. How much strength was he using? He told me about forty percent. I remained relaxed, no tension in the muscles and simply stood. I was pleased the root held.
A few days later I discovered one of my students is a college champion wrestler (number two in the country). Another experiment. After a chat, he agreed to push me and try to find my center and unbalance me. We pushed for ten minutes or so. I relaxed into my stance again. Each of seven times he was unable to unbalance me. Seven times he lost balance. He repeated a number of times, "How did you do that?" I simply smiled.
It's not magic, it's taiji.