Waage [27][29] has proposed a real-time dynamic just intonation keyboard system. This system tunes the note produced by a key according to what other keys are currently held. As Doty points out [7] and Waage concedes [28], a major limitation of this system is that it only considers what keys are currently pressed down, whereas information about recently-depressed keys could cause it to make ``smarter'' intonation decisions.