I fight my infantry in three ranks, simply because to do otherwise is to lose a third of its firepower along a given frontage when using 'fire by rank'.
As far as squares are concerned. I consider it entirely correct that infantry in square should be able to kill cavalry with virtual impunity. The problems that arise with squares are entirely the result of the badly programme 'BAI'.
Firstly cavalry should NOT charge into a formed square, and therefore, should not get themselves massacred by doing so.
Secondly, cavalry should impose a major morale hit on any unit it threatens that is disorganised, more so than if that infantry had remained in steady and in line.
This would force players to make a much earlier decision on whether or not to form square and recreate more accurately the dilemma faced by real life commanders when threatened by cavalry. As things stand you can actually wait for the cavalry to charge, or even make contact before tapping the 'square' button which in practice ought to be effective suicide for your infantry.
Hitting 'Form Square' when cavalry are already in contact ought to be the virtual equivalent of 'Run for the hills' and result in an almost instant and guarantee'd rout.
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