The Makedonian phalanx -- why such depth?

[Macedon]

OK, I meant right of shield over left of shield, but that is just jargon. Yet, it is interesting that most reliefs and paintings present the opposite overlap, isn't it? Were is this discussion btw? Would be interesting to see what most people advocate... but yes.. I much prefer that overlap when in line. It really helped us keep ranks and push, especially during charge, when the other overlap would many times end with individuals moving their shields too much opening gaps and breaking off when pushing.