Take note that even without drawing the bow to its full extent the arrow could easily penetrate through mail. Not sure about plate, very few arrows could penetrate that + the other layers beneath.
Please take also note that this technique was almost never used. It wasn't efficient to shoot like that, given the low number of arrows each bowman had. Volleys were far more efficient morale-wise, too.
Plus, only horse archers really used this technique since they were fast in-fast out skirmishers. Even if they fell from horses they could release a shot(talking about mongols here). No foot archer learned that technique, it was designed for horse archers.
