I strongly disagree.

My starting spartan unit often leads assaults (especially on Korinthos on turn 2), and doesn't take too many casualties. I often have that starting unit of Spartans as an elite reserve for several game generations to come.

The KH's other infantry is amongst the finest in the game IMHO. You can't use them like the Romani or Successors. The KH general should focus on pinning with classical hoplitai and flanking with peltastai, light hoplitai, and whatever cavalry is available.

You'll lose out if you don't move quickly. The Mak troops are superior for the most part.

Although the KH general's bodyguard will give any unit in the game, save elephants, a run for their money.