I don't understand the part where you talk about 'columns'.
Do you mean the vertical ( perpendicular ) line on the grid or do you mean the area defined by the two vertical lines on the grid ?
"The dots on the grid are most accurately depicting the slope of the green where the center of the column is (or underneath the center of the column)."
Not sure, maybe the center of the grid but directly underneath where you hold the green arrow/aimer /pointer. So when you use the pitch option and move the pointer around, it centers the grid/slope/break of the spot where your putt will roll as it passes that part of the green. It's not so much reading the pitch/putt view always, it's just that it gives you a different perspective of how to read putts. Maybe one that's "the right way," but that's debatable I'm sure.
This isn't meant as a complaint, but does WGT place a bit more emphasis on the break at the start of the putt than real golf, or only on some occasions? There's food for though for ya :D