I have heard of this, but don't like it. The long drive should be measured from the tee, not the green. For "ties", we would go with the most accurate which would be from the center of the fairway.
I've played many long drives as length minus the distance from the center (the white line down the middle of the fairway"). That rewards length and accuracy.
But for the league, as long as everyone agrees, it can be anything they want.