My theory is Flamini was originally brought in as defensive minded M C (midfielder centre) or DM C in Football Manager terms. When he was asked to fill in as leftback or D L, it was during dire circumstances when the squad was so short that amongst those fit to play, he was the most capable one around who could do the job.
It is like some strikers who have started out their careers as centrebacks due to the similarities required for playing those positions, being big, strong on the ball, can read the game, etc.
Fast forward to the present, there is Gallas who has often willingly and capably played as leftback. Although he is fussy about where he was going to play when he left Chelsea, the fact is he has played day in day out over the back four positions over his career. Why he chose to bring up his future playing position to spite Mourinho is another matter for discussion and speculation.
In short, I think Flamini doesn't see himself as a leftback or want to play in that position long-term. Djorou being another youngster in Arsene Wenger's plans is being given a chance to prove himself. Phillipe Senderos has proven to be quite capable last season, now that he is injured, what better time than now to slot him in the first team squad.
Wah suddenly after writing this post I think can go and apply for the ESPN presenter job... you know, the show before the match starts, with Jamie Reeves, etc... HAHA
