Wolfgang,
Thank you for these links.
I realise I am asking you to speculate here......
Am I correct in saying that the hills are so far away than one must be exceptionally below the normal approach over the hills to be anywhere near them? From a published chart on this forum the WSW sector has an IFR level of 7900 ft over the hills with a minimum safe VFR altitude of 3500 ft? (it is badly readable on the link). So much so that a QNH/QFE mistake would not lead to a CFIT accident?
What would be the effect of the MATZ coming from the west? Do people normally route around it? Or over it? or do they transit the MATZ when joining from the west for the procedure?
I understand the pilot knew the airfield quite well, so I guess he would have adhered to local procedures?