Using a closed stance or square stance, I have problem (not enough) rotating my left arm after impact and the ball goes to the right. I experienced the open stance today, and because of the open stance, my alignment will become: left wrist directly (prependicular) facing the target; open shoulder, left arm straight. Because of this, I guess when I hit, at impact, it is easy for the left arm (wrist) to roll, right arm extended straight to the target line and the ball will go straight.
Is that because I am unable to turn fast, or not flexible enough such that will find diffculty squaring the clubface using square stance?