Double-click "g" not working as expected I'm new to Blender and used a boolean to cut into a shape. Now I'm trying to get rid of "n"-gons by using double-click "g" to slide "excess" edges along a face. 

The trouble is that when I slide the edges:


the old edge remains (I made sure in the outliner that my object is the only object in the layer, i.e. I think there are no other copies -- specifically, the Outliner shows "Plane.003" and then when I click the "+" to expand, there's a "Plane.017" below it, but all my "Plane.00n" objects on other layers have "plane.00m" objects attached to them. Is this normal behavior?). 
the edge that's slid seems to go out of the proper orientation when it's slid in one direction (but not the other).


Any ideas what might be going on? Thank you!
While you're waiting for an answer, you can try using Shift + V. That's an alternative hotkey to slide edges in Blender 2.79.