I knew my front LH G4 coilover shock was leaking oil so had a chance this week to remove it from my AW11.  Now off the car It feels almost useless compared to the RH good shock with no leak.
 
With a skilful friend who made tools suitable to pull the G4 shock apart we discovered that someone had been in before us by the obvious damage to the 4 recessed pin holes in the top gland nut.  We found some internal broken pieces which would explain why it has failed. 
 
It maybe possible to repair this shock but I am going to need some parts so if anyone has some old D2 or G4 coilovers lying around going cheep please let me know.  I would assume that the SW20 version of these shocks will have the same internal components.
 
Also a big thanks to Steve and anyone else involved with MTC2015, I had a great time and want to do it again in 2016.