Slitherine

Newbie question:

The Garde/Federe Nationale/Volunteers "Line Infantry" of the French Amree du Nord (1792-94) in Emperors and Eagles states:

"At least one, and up to half of the Garde/Federe Nationale/Volunteer units MUST be in Skirmish formation. They are treated as in Skirmish formation in all situations except that they fire as Reformed Line Infantry rather than Light Infantry. Units selected as Skirmishers MUST remain in that formation throughout the battle"

How can Line Infantry be in Skirmisher? Is this an 'over-rule' where normally Line can't be in Skirmisher, but in this specific case they can, or am I missing something?

Being in skirmish formation brings its own penalties and benefits - more manoeuvrable and harder to hit, but vulnerable in close combat especially against cavalry as they can't form square.
Light infantry shoot better than line at medium range - 5 dice rather than 3.
Having these units act as skirmishers but shoot as line is to achieve a certain combination of behaviour I would assume. It is not that these units can be in skirmish order, they must be.
Some units (such as Austrian Grenzers) must always be in skirmish order, but they are actually light infantry and shoot as such.
You are correct, this appears to be a one-off situation, to simulate a rare and temporary "training" level for these troops.

Yes it is special and if you read the narrative at the front of the book you will understand why, we did this, which was to model the behaviour limitations and tactics of the French Republican armies of 1792-95.

Saxonian wrote: ... but vulnerable in close combat especially against cavalry as they can't form square.

- although mainly in theory I think. It's very difficult to catch skirmishers in combat, and IMO they are actually often safer against cavalry than troops in tactical - they don't need to take a CT when charged and with a little careful placing can virtually always evade safely away.