I was jumping with modified military chutes back in the 70s. We weren't instructed to release our mains. Only one of us in our group ever used a reserve. He found a way to do something wrong on every jump. On one jump, when he jumped, he was doing back flips from the plane. His chute deployed into a classic Mae West. He got so excited, his hands were shaking so much he couldn't grab his reserve handle until he took one had to steady the other. He pulled his reserve and it opened fully. With 2 chutes up he was dropping so slow that he was drifting out of the drop zone toward the power lines. We were taught you can't steer with 2 chutes deployed. Well he was pulling like crazy and found he could steer enough to get away from the power lines.