I find phalanxes utterly impenetrable from the front. I usually deploy them in a very long line, even if i have to weaken the phalanx by spreading it out I will still match the enemy line's length whenever possible. Then I support the phalanx with missile troops, and attack the enemy's flanks/rear with cavalry and mobile infantry. The only time I eve have my phalanx running into trouble is when they face enemy phalanxes, otherwise even elite units seem to end up decimated without having achieved anything. Phalanxes are uber.

Maybe you're using Iphikratean hoplites, though--these are alot less good because they have shorter spears, and what makes phalanxes so strong in the R:TW engine is that they hold the enemy at spear-length. Also, never attack Macedonian-style phalangitai with Iphikratean hoplites, or other short-spear phalanxes. All other units will fare better.