[Retros] Solidarity chess (=SC)

[Eric Angelini]

Hello RetroFans,
a (new?) chess variant here (in French, sorry) of mine:
http://www.cetteadressecomportecinquantesignes.com/Solidaire.htm

In a few words:

When you play "Solidarity Chess", you have to keep all the squares
on which your pieces are "glued" together to form a single territory.
A square is glued to another one by a side or a vertices. 
The other rules stay the same.

You are not allowed to start a game with e2-e4, of course.

I'm sure this new constraint can provide a few good ideas to the 
retro genre (like: Is this position legal in Solidarity Chess?)

I ask for instance --on the above page-- to build the shortest 
SC proof game leading to a white promotion (I'm not sure, though,
that my 12-move solution is the shortest one; I'm only working
on this since Monday).

Best,
É.