Weightless Surgery

BBC

The whole idea confounds me. What they did was set up an operation in one of those planes they use to get people used to weightlessness. However, weightlessness only lasts 20 seconds. So they had to stop after 20 seconds and wait for the whole thing to start again. I understand why they did it, to get a rough idea of what it would be like to perform surgery in space, but I don't get the last part of the article about applications here on Earth.