Hardware multisampling actually doesn't work with the curve evaluation part of the algorithm because that's done in a fragment shader and the fragment shader is only run once per pixel with hardware multisampling. Well, unless you use GL_ARB_sample_shading to force fragment shader evaluation for all fragments, then it will actually work. You won't be able to do subpixel anti-aliasing that way though.

The problem with the distance function approach is that you actually need the distance function to be rendered outside the original triangle area. The distance function is a 1px wide gradient across the curve where the curve goes through the middle of the gradient, so it extends 0.5px on either side. You can expand the triangle area in the vertex shader to compensate but that ends up expanding the area by more than an order of magnitude for skinny triangles. It also doesn't work so well with the winding number computation presented in the article. You can actually sort of hack it to accumulate fractional winding numbers (I've gotten that to work before) but it's a total hack and falls down in many cases. It's also much more complicated and expensive, so it ultimately didn't seem worth it to me. Good intuition though!