Re: Tool to help draw a grid?
Sparrowhawk: I would guess could use your method to make a far less detailed drawing too, by starting with one shape and then working outwards, without necessarily taking each shape to completion. One would then end up with a line drawing that can be filled in with more tone.
Still not sure how one would go about trying to create a complex composition in this way. And it surely requires great accuracy, because even the slightest error will perpetuate itself through the entire drawing.