I've been getting this a lot
the method I've been taking is to delete the face I'm dividing then draw the dividing lines in, then selecting each subface to remove any extra faces using the delete tool.
at times I've had 4-5 stacked faces that I've had to remove before I started doing the above.
oh and an easy way to find stacked faces other than the Xray face mode (stacked faces show up darker) is with the paint tool.. if a face won't paint, it's stacked...