No need to.
Dialog is always recorded Mono. This is mainly because when mixed, dialog is usually set dead center of the mix so it is easily understood and reproduces easily on virtually any kind of speaker system.
Recording stereo dialog is jarring for the listener, as the “placement” of the person after a cut to a different angle is a dead giveaway. A stereo recording would change from each cut, as the audio would follow the picture. In addition,a stereo signal ties the hands of the mixer, because they are bound to the environment that the stereo recording was made in.
In the mix, we’ll pan if the off screen direction calls for it (i.e. running across the screen, would require a subtle Pan to match onscreen action).
The only things ever recorded in stereo are ambiance or Foley / SFX, and that is still not a guarantee.
.: michael kammes mpse
.: senior applications editor . post workflow consultant
.: audio specialist . act fcp . acsr
.: michaelkammes.com
.: michael A T michaelkammes.com