OK so we have two different issues here. One is what affects a unit to rout and what affects it during the rout. The decision to Rout is first kicked off by a UnitMoraleCheck() function. This occurs each minute. I won't go into all the details as the algorythm runs for 500 lines. Suffice to say that yes it factors in nearby friendly ( and enemy ) retreaters. It determines the differential in retreat/rout personnel between friendly and enemy troops. The adjustment applied to the morale level will vary between 10 and 40%. Typically if there were 300 other friendly retreaters/routers nearby and no enemy then the effect would be to reduce the morale by around 16%. BTW the function also factors in the presence of a nearby superior HQ, adding in a mod based on its leadership, which could be negative if the guy is a jerk :).
Thanks, that´s quite valuable information! I´d already assumed, that presence and distance to friendly units/HQ plays a larger role in rout triggering (well, should´ve been obvious anyway).
So a more isolated (from other friendly) unit, is likely to get a rout trigger more oftenly (other factors left aside). Is physical distance a matter, or just visual distance? In example, two adjacent infantry Coys in a thick wood do not have LOS to each other, will it help to broaden the footprint of one or both, so they get in visual liaison to each other? Does that help for rout triggering, or avoiding?
Would be nice if statements like yours above, make it into the game manual anytime.