Now, this one I actually do have a hard time seeing balanced, like that. Wouldn't it have to be even more vertically posed, so not to fall on its face? The tail seems to offer next to no counter-weight, even the belly is positioned in front of the pelvis, and would pull it forward, at least from what it looks.
It helps to see it in 3D (like in a skeletal mount). The belly is widest just in front of the pelvis, and the guts continue into the pelvis on these guys. As a result the CoG should be almost exactly where the front foot is placed (remember it's walking, so it's not in perfect static equilibrium).
that analogy makes a lot of sense to me- I believe that ground sloths, therizinosaurids, and perhaps prosauropods follow a very similar body plan due to fulfilling the same ecological niche. I wonder if someone has taken the time to name such specific niches?