Hi Last Hussar. Infantry skirmishing formed a massive part of discussions in the development of v2. I'll try and summarise:
1) In version 1, LI units and infantry skirmishing was deemed to be a bit'broken' from a competitive play perspective – at least according to some tournament players.
2) Historically, entire regiments/brigades rarely formed skirmish formation. There was normally always some part of each battalion, or a battalion in the brigade, that was kept formed up for the skirmishing companies to rally back to.
3) The v1 infantry skirmish formation depicted whole regiments in skirmish formation, allowed the entire regiment to happily slide sideways, backwards or on an angle, and allowed an entire regiment to evade from an enemy assault. This seemed to have more in common with ancient horse archer tactics than Napoleonic regimental level LI tactics.
4) Part of the philosophy behind v2 was to (where practicable) simplify the v1 rules.
5) 6MU 'skirmish' shooting in FoGN represents a cloud of skirmishers out in front of the unit popping away at the enemy. It was decided that the simplest way to model LI was to do away with the infantry skirmish formation altogether. If assaulted/forced back/fleeing, the cloud of skirmishers in front of the unit are simply falling back to rejoin the supporting formed up unit, which is modeled on tabletop as being formed up in tactical (or extended line) formation as modeled on the table.