How do I use hoplites?

[c4liban]

Can someone explain me when to use the "attack in formation" and the phalanx mode? From my understanding,I should use phalanx when the enemy is only straight infront of me and take the unit out of formation when they are surrounded. But what happens for example when I take them into phalanx but out of formation? Do they still get the buff from phalanx? And is it correct that unit get a moral buff when staying in formation?
Would be nice if someone could explain this.

[Dresden]

It is always best to keep them in formation (phalanx). You also need to tell them to attack when in phalanx.

[c4liban]

Even if they are flanked/surrounded? And a quite similar question about for example the greek swordmen. When you use Shield wall they move closer together. Now when I take them out of formation what happens to their buffs?