Quote Originally Posted by nameless
The major problem with the Phalanx is its inflexibility. Your talking about 100(dunno the actual number) guys with 15ft spears in close formation having to straighten up and pivot to the incoming danger which is incredibly difficult to do as they have to do it all at the same time and even so then they'll just expose another flank.

It's basically a massacre if someone smashes into its flanks because technically they can't defend it without exposing another flank.
I'm not saying the whole phalanx should turn round, just the rear most ranks to face the threat.