As you saw in the previous episode, when Colonello put Tsuna through his training, there's one big problem: Tsuna can't swim at all. This episode addresses that issue with the help of several of Tsuna's friends. Each of them has their own teaching techniques, and they're pretty odd. Should you skip this episode? For first-time watchers, I think it's fine to do so. However, for those who have watched the series several times, I think there's a little bit of foreshadowing for a future episode which I pass it off as some sort of a gag. Or am I just overanalyzing things? P.S. Just one more episode to go before the next arc begins!