[ethan]

This might have been the worst possible way you could perform this experiment. What if he accidentally drew over the same line twice? What if there are uneven darknesses of the filled-in letters? What if one pen has a lower flow of ink than another? What if he left a gap somewhere?

Why not just use calculus to determine the area inside each of the letters?

[amoeba]

While his approach is unlikely to be close to the true ink efficiency I give it points for a being a creative way of representing the relation.

[ztravis]

I would guess they actually did this first (determine the area directly) so that they could judge how large to make their sample word. Their results look very nice and, notably, are scaled appropriately to a single ballpoint pen's worth of ink.

or maybe not. might have just turned out well!

[lallysingh]

Or draw them in memory and sum the pixels in (inverted) greyscale?