The fourth path to attaining arahantship

From the Yuganaddha Sutta , there are four paths described: 1. Development of insight preceded by development of tranquility 2. Development of tranquility preceded by development of insight 3. Tranquility developed in tandem with insight 4. **Mind's restlessness concerning the Dhamma well under control** From my understanding, the first three are about vipassana (insight) and samatha (tranquility). Questions: 1. How does the fourth path work? Please elaborate on the fourth path. 2. How does one practise that? Please provide details. 3. Why is vipassana and samatha not required on the fourth path? > Ven. Ananda said: "Friends, whoever — monk or nun — declares the > attainment of arahantship in my presence, they all do it by means of > one or another of four paths. Which four? > > "There is the case where a monk has developed insight preceded by > tranquillity. As he develops insight preceded by tranquillity, the > path is born. ..... > > "Then there is the case where a monk has developed tranquillity > preceded by insight. As he develops tranquillity preceded by insight, > the path is born. ..... > > "Then there is the case where a monk has developed tranquillity in > tandem with insight. As he develops tranquillity in tandem with > insight, the path is born. ..... > > "**Then there is the case where a monk's mind has its restlessness > concerning the Dhamma [Comm: the corruptions of insight] well under > control. There comes a time when his mind grows steady inwardly, > settles down, and becomes unified & concentrated. In him the path is > born.** > > He follows that path, develops it, pursues it. As he follows the > path, developing it & pursuing it — his fetters are abandoned, his > obsessions destroyed. > Yuganaddha Sutta