Gentlemen,
I have been involved in two HPS multi-player games using single phase system. I have observed what I believe is the short coming to the HPS Single phase system. When units attack from covered positions (the Rebs) they experience little AI movement fire (relatively speaking certainly not 100% of those that can fire), they close on the emeny (the Union) and then fire in good order against the enemy. On the Union's turn, before they can fire in full effect, they experience the first routs due to enemy fire and the remaining units are disrupted and fire less effectively. While the return AI fire is from undisrupted units. In subsequent exchanges the attacker (the Rebs) have the advantage due to not being disrupted while the defender (the Union) is disrupted. So by attacking first you disrupt your opponent and gain the advantage due to a low AI percent counter fire. The solution to return the true advantage to the defender would be to have the AI fire during movement and then all units that did not fire during movement phase fire during a defensive fire phase, before melees are determine or before disrupted status is determined (perhaps after the end turn button is clicked); so that all units that are able to fire do fire before they are disrupted by routs. Would be nice if HPS could fix this and is the reason I play all my solo games in phases. My two cents worth.
Lt Gen Joseph C. Mishurda

Lt General Joseph C. Mishurda,
"Killer Angels"
XXV Corps, AoJ