Smartxx is the chip I got. I couldn't be happier. Great chip and WAY ahead of everyone else in terms of stability and features (the others are finally just now catching up after six or eight months and Xecutor is probably passing them now).
Anyway, point is, I DID use the underside alternate D0 and took a picture so everyone can see what you're talking about. Keep in mind that this is the alternate, "easier" solder point. The one on top is even smaller. The penny is there for scale so you can see just how big this is (about the size of one of the letters in the word "Liberty"), and there are traces running along each side which you cannot let any excess solder flow over. Definitely a pain in the ass.
All this while you hold the wire in one hand, the solder in the other hand and the soldering iron in your third hand. Kinda tough.