Plane Problem

 From:  NightCabbage
OOOHHHH! That's what you mean by "trimming"!!

It literally trims a part of the surface to the shape that you want! Hah! That makes sense now.

Ok, so that makes sense, but still, shouldn't I then be able to adjust the trimming edges?

Also, perhaps I should be using something like Network instead of Planar for this kind of thing?