1.4.3 beta there is a bug where if you place a group of troops in loose formation you can't get them out of it; they retain this loose spacing even if you put them in a different formation. To make matters worse, this 'infects' others groups. IE you set Archers to loose, infantry to shieldwall. Infantry will be loosely spaced while holding up their shield. This bug also occurs in village scenes by simply moving a troops group. I've already reported it & community supports passed it along.
Side effect of the new shared troop XP: doomstack tier army composition, atleast for AI minor factions. In particular, the Ghilman faction is becoming 70-80% composed of their tier 4 troop. This unit has cataphract & mameluke armor on (at 1 tier lower). See image