a minimal amount of micromanaging = victory
I guess You never fought Huge battle with HA.
I played one as Haysadan.
1400 HA with small amount of heavy cavalry vs Ptolemy 3500 Heavy Infantry and some Heavy cavalry.
If You have terrain obstacles on the map it makes very little room to manoeuver.
You end up with micromenagment nightmare.
After this battle I stoped using pure cavalry armies.
They served me well for first 25 years and If You are Zen master and dont mind fighting the same battle 5 times (because You and up with no arrows) are quite good tactic.
But as said it requires ridiculous amount of micromenagement.