The shoe is a whole cut derby. The problem is laying the sides over the front. This is usually done (like in those Aldens) by adding a small piece, to take the eyelets and go over the tongue.
Alternatively, if the set-in pieces are not used, you have the effect of those shoes by Jan Myhre. You see the cut in the upper leather, then the tongue is set-in a level lower.
Lattanzi has managed to have the sides overlapping the front, only by a few mm, I presume, but nevertheless, they overlap. You can see where the tongue is joined, right under the lacing. How Lattanzi did that, I have no idea (maybe by sheer force of will). Particular remarkable is the use of grained leather: too heavy manipulation, and the grain will smooth out.
I wouldnt be surprise at all, if the shoes had no back-seam (I cant see it in the photograph). They are an absolute tour de force in leather manipulation.
For more detail pictorial illustration see bengal's original post: