How to use infantry bodyguard?

[Moros]

3. Saba: I guess the general should be kept as a reserve elite infantry. They are quite mobile so you can run up and down your battle line. When you see an opening or your own line is crumbling send the general in. He should act as a deciding factor in battle and most likely his heroic fight will break the enemy morale and from that breaking point you can crush the rest of the enemy army with local superiority.

Now you're already making me think of tactics for the Sabaeans in EBII, which will have a rather different and much more varied army.