Well, your super-soaraway bonus post for this week....
Consider this: southern Greece is hilly and lumpy.
It is not ideal for phalanx warfare.
So why did it happen like that?
As ever, a combination of factors - the Greek farming year, the formation of the polis, the natural boundaries of the city states and so on.
The boundaries of the states usually tended to be on mountain ranges. But the Greeks never blocked the passes against other Greek states. The attitude seems to have been 'OK, let them come and then we'll sort it out like gentlemen.' Military roads across the borders were built by the advancing army, and they were permitted to do this unhindered.
Until the 430's, there seems to have been this attitude. Similarly, sieges were not a factor in Greek warfare. Hoplites were not, strictly speaking, designed for assaults, nor were the armies large enough to blockade. So unless there was a handy traitor around (not unlikely) cities couldn't be taken.
So early Greek warfare seems to have been a fairly straightforward affair, but why did it happen like this? The answer seems to be cultural. There were the ideals presented by Homer, religion, with sacrifices due to various gods on making and moving camp, setting out from the city on campaign, and before the battle itself. Bad omens prevented battles or movement. This must have made greek campaigns a somewhat frustrating affair, but we do know, for example, that the Spartans were late for Marathon on this basis.
The point I'm trying to make is that even though our culture is heavily influenced by Greek culture, it dosn't mean that we actually understand the mind set. Western philosophy may be 'footnotes to Plato' (Alfred North Whitehead), but that doesn't mean that Plato would understand us.
Spartan armies (and presumably other Greek armies) set off for battle with large flocks of sheep, to provide the sacrifices. How many baggage elements for Greek armies have you seen of sheep? Ritual, sacrifice and the gods were important to the Greek soldier. The rituals would have to be completed correctly and the omens good, or the soldier killed in battle may not have recieved the honour due to a hero.
Funnily enough, the omens immediately before a battle were always good. I suppose that is why professional seers also accompanied the army. Sticking a knife into a sheeps throat and observing the direction of the blood (presumably towards the enemy was good) is an advanced skill, or at least, getting it 'right' would be a real seer ability.