Abbott's rules are successful, I feel in making effective command and control as important to victory ad combat outcomes. Brigades are given orders by Division (and Corps) commanders at the beginning of the game and these can be changed under certain conditions. Brigade commanders can also request an order change by sending a messenger with a status report to his superior.
The combat mechanism is fairly simple based around opposing d6 rolls modified by the presence of leaders, terrain, the level of fatigue of the brigade and morale. Combat losses are essentially reflected by a build-up of fatigue at the Brigade level each time a regiment is in action. As the fatigue level of the Brigade increases it can effect the combat factor of the unit (called its 'volume of fire') and the morale status.
I used an older version of the rules (attached as a PDF at the bottom of the page linked to above) win which Brigades (and divisions) must pass a morale test every turn. A 2012 update moves away form Brigade and Division morale checks. Instead, the units fatigue and morale impact on the brigade's capacity to activate each turn.
Overall, I feel the first use of these rules gave an interesting game and I really liked the 'orders' mechanism and the inevitable consequence of the build up of fatigue. The impact of sustained combat on brigades is well modeled by the fatigue rules - a nice touch. I felt it gave quite a good 'feel' for the challenges faced by brigade and divisional commanders during the Civil War.
As a first time player, I did find the occasional situation where the rules were not explicit. For example, it was not clear on the difference between mounted an dismounted cavalry (except a reduction in movement for dismounted).
One of the difficulties I had was around understanding the impact of varying morale levels (disordered, shaken, beaten) on game play. Again, I believe this is addressed by the new activation system. There was a bit of record keeping (orders, morale status, commander ability and troop quality) but with a little planning and some more subtle on-board counters and a simple roster sheet, it would be handled easily.
|Brigadier General Tyndale's Brigade deployed in line of battle with a small reserve and his right flank holding the heights.|
|From the SE, elements of Anderson's Brigade pursue the remnants of a Union division that fell back after an action that earlier that morning.|
|The Union relief column cross the stream and the cavalry swing wide on the left flank. Tyndale's Brigade has hold orders while the cavalry and artillery have orders to advance to Tyndale's left flank and hold.|
|The Confederates deploy into line. The final advance begins.|
|Tyndale's Brigade have rifled muskets so get the first volley in as the Confederates close on their line.|
|The Union troops are spooked as the Rebs advance and their musketry has little impact.|
|The musketry of the Confederate left flank finds its mark and the forced a Regiment back over the crest of the hill. On the Union left, the artillery unlimbers at the foot of the hill.|
|The musketry over the next couple of rounds takes a toll on the Brigade commanders. Tyndale is out of action for a full turn. The Confederate Brigadier, Anderson, is shot from his horse and falls to the ground, dead.|
|The last remaining Union regiment has to fall back under sustained fire from the Confederates.|
|The Confederate advance falters on their left with a regiment driven back form the hill-top. Moral on both sides is beginning to falter. Both sides are now shaken but the Confederate advance pushes on.|
|The Union cavalry assault on the left fails. The Union morale falls again - Tyndale's Brigade is battered!|
|A Change of orders on the Confederate right redirects their attack towards the undefended artillery. Brown's Brigade (Confederate left) keep up the musketry on the Union troops that have now fallen back to the stream.|