Phalanx

[Sean Manning]

They did, Spartans in particular did or attempted this many times. The problem is that a phalanx does not easily lend itself to the type of small unit tactical flexibility needed to pull off such a manouver. If you bend your line around your enemies flank, often your line on the right extended beyond theirs on the left, then you just expose the flank and rear of your own troops to any enemy troops on the phalanx's flank.

Thats what i don't get its clear the drawbacks that you have stated above but if you can see that the no doubt they did. All you have to do is put your Phalanx in front of another, hold it and send a seperate force( not necisarily another Phalanx) to attack the sides, job done. I can't be that simple.

Well, are you sure that your psiloi and cavalry are going to be able to beat their psiloi and cavalry (who will be protecting any flank which isn't anchored on rough ground)? If your cavalry win, will they follow the plan and attack the enemy in the flank, or run off in pursuit? What if some of your troops or their troops rout while all this is going on? If you use your hoplites to form the flank attack, will that weaken your main line too much? There are all sorts of complications which made outflanking the enemy hard to pull off.

Anderson's book Greek Military Theory and Practice in the age of Xenophon has a good write-up of Greek tactics and why they worked the way they did.