From what I see in the video, there are few lessons to be learned for inexperienced tunnel flyers: 1) Go through more individual stability drills before attempting 2-way in a small tunnel. Be able to hold your spot (both horizontally and vertically) with confidence even if the other person pushes you or steals your air. 2) Unless absolutely necessary, perform 2-way reasonably close to the net and never allow big altitude differences between individual flyers 3) Under all circumstances maintain visual contact with the other person. Throughout the whole video the guy in blue suit rarely watches where the red guy is. Especially when flying with beginners it will be fairly frequent for them to fly into your burble, so you have to be aware of them and avoid if necessary. They may be panicking so do not assume they will avoid you by themselves. Wish you a speedy recovery!