When it was to their advantage, they made a forward move; when
otherwise, they stopped still.
Mei Yao-ch‘ên connects this with the foregoing: 然能使敵若此當須有利則
動無利則止 “Having succeeded in thus dislocating the enemy, they would
push forward in order to secure any advantage to be gained; if there
was no advantage to be gained, they would remain where they were.”