Thank you for your answers. Especially Refraction you had a very nice well thought out explanation. I have to agree that the strongest reason was for Gon's training. But I guess the main reason for my suspicion was that they risked a lot in this. It was not only Gon but they also had (I forgot...
Gensuru was obviously extremely strong and lost because he greatly underestimated his enemy and Gon was well prepared. But throughout the fight it felt somewhat obvious that Gensuru would not stand a chance against Biscuit. First of all, say even if she was not at his level - she could have also...
