Originally Posted by Peckish

It doesn't really have anything to do with whether I sew it on my hand or machine - I simply don't press my bindings in half before I sew them on. I find the fabric wraps much smoother around the raw edge of the quilt if I don't press, and it looks and feels nicer.

If you think about a high school track, the inside lane is shorter than the outside lane, right? Now imagine the binding, as it wraps around the quilt from the front to the back, is like that track. The inner lane (the inside layer of the binding) is shorter than the outside. If you don't press a fold into it, the fabric has the ability to shift and adjust to lay flat and smooth against the quilt. If you've pressed it, it has a memory and will want to stay in that position, which results in the "inner track" being the same size as the outer track, and you end up with excess fabric inside your binding.

Just my personal preference, to each her own.