According to the res Romanae putting your hastati and principes on guard mode is a good thing; "Order Roman hastati and principes to use guard and fire at will modes to make them behave historically and very effectively. Form them up in parallel lines for best effect."
Has anyone had any sucess with this? I tried it and I found units engaged in melee tended to slowly reform slightly out of the melee with their backs to the enemy. Very handy.That happened in two of my three quick test games; the Romans threw their pilums without trouble, then charged and started killing very nicely. Then the individual men slowly ebbed away and reformed the unit with the back to the enemy. With guard mode off they threw their pilums without trouble, charged and kept on killing until the enemy routed and I ordered a halt.
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