He continued to immerse himself in the water for a very simple reason.
That was to increase his Swimming Experience Value and incidentally practice his saber technique.
Although his saber skills couldn't be used even if he broke through again, and even if he mastered the explosion of the Nine Layers of Strength, he still needed to go into the water for the sake of increasing his Swimming Experience Value.
[Skill]: Swimming (Perfection 793/1000)
He only needed a little over two hundred points to reach a thousand points of Swimming Experience Value.
He was full of anticipation for breaking the limit of his Swimming skill.
Moreover, the Swimming Experience Value increased very quickly. Based on his understanding over the past few days, he would only need to stay in the water for a little over two hours to earn those two hundred points.
Since going into the water, he might as well practice his saber technique, so as to not waste time and maximize efficiency.