Concealing Infantry movements

[sulla felix]

I agree Calvus,

Caesar's men needed to win or die of starvation or thirst -great motivation!

Also do not underestimate the confusion, noise, dust etc. on a battlefield. The slightest hint that things are not going too well (eg. seeing cavalry returning bloodied and battered) would lead to widespread panic in the rear ranks and reserve forces (the non-Italian allies are a prime example of this as noted by Appian).