I think it's quite different for officers and NCOs but yes,
estab plays an important part of it all, porbably just below
performance. Both levels go through a somewhat fixed advancement
route with certain appointments that must be fufiled in order to be
promoted and get to the next level.
But being a rather small establishment, there are limited spots for
certain appointments and not everybody can get there. That's where
performance, and maybe some arse-kissing, comes in. 
