These rules up the scale of even Big Bloody Battles, to which they are comparable. A stand has a mass between 1 and 6 each point is roughly 400 men, several stands make up a brigade/division, so a Crimean Russian division of 10,000 men might have 5 stands of mass 5, whilst a Boer brigade of 1600 men could have 4 stands with a mass of 1. A target's mass is used for firing if dice score + mass = required nember a hit is scored same for melee except you use your own mass. So the Russians would be shot to bits by the Boers but would sweep them away if the got in. There are adjustments for quality, cover etc in the shape of extra dice.
Command, as always, is key. A variable number of orders may be given each turn to Move, Hold or Rally, but once a unit is engaged in a fire fight it is locked and unless you wish to charge or rally will not need orders.
To get this subtlety into 2 pages of A4 is very clever, and for the price it is worth owning them even if you do not plan to refight Gettysberg or Solverino.