this is a good discussion. What is the general consensus on using the grid.
To me I don't think much about the math or science tie in. It seems that having
someone zero in on a small area such as a grid square will help them see
relationships that are vital for observational drawing. Though it's a 2d surface
it still seems like a logical preliminary step in teaching drawing whether
observational or not. Maybe seeing these relationships in 2d should be taught
before observational drawing is introduced.