The "double corded" style paints one side of a cord red and the other blue. The problem comes when the pattern changes what side is which. You can play around with it to see - put in some breakpoints and you'll see the "sides" switch on some cells. This can't be done with tiles.
The tile manipulation is actually no simpler than drawing SVG, because the hard bit is calculating the entry and exit points for each tertiary cell. And SVG produces better results :)
I also plan on doing some more stuff with it someday - like deforming the grid by moving the corners. This is pretty simple with SVG but would be really hard with tiles.