The Lorraine Opening is the fifth most popular French opening and 27th Overall, and the last opening that is used in over 5% of games.
When playing France and the manure is heading toward the ventilation device, this is an opening that you should seriously consider. Otherwise, best to avoid giving potential allies a reason to start throwing it.
Moves north can be very aggressive ones for France, and this opening can become a solid attack against either England or Germany if it is allowed to go unchecked. For this reason, opening with it is likely to cause the two to consider working together very strongly, a situation that needs to be avoided for France to have a good game. This rules out the Lorraine Opening in all cases. All apart from one.
When you are sure that both your neighbours are out to get you and intend to open strongly against you, this opening is a commanding defence. While the threat of Italy in Piedmont is still a concern, the rethink this opening may cause in an aggressive alliance looking for a quick kill is powerful benefit.
The downside is that there are probably better options: the Alsace Opening (where A Mar s Par – Bur) and the underused (and so far unnamed) opening of (A Mar – Bur; A Par – Gas; F Bre – Ech) which is inexplicably only the equal 312th most common opening! Both these opening have most of the advantages of the Lorraine but ensure coverage for Marseille and the acquisition of Spain in Fall 1901.