Hi all, I think this may have been mentioned before but I feel that troops in entrenched positions or dug-in in urban terrain seem to retreat far too quickly when subjected to incoming fire/barrage. Confident troops in good cover will not 'bug out' as they seem to in CO2. There are plenty of historical events where infantry refuse to be dislodged by artillery alone, in the 'Hurtgen Campaign' a German infantry unit was subjected to a barrage from dozens of battery's for over an hour and was only kicked out once US infantry assaulted. 
