when this era of aircraft were designed and the manuals written the system was completely different. They were maintained by fully skilled people. The manuals didnt specify every task the way they do now. I was in KSA for the start of Hawk ops using the old USAF trade system. The manuals didnt comply so we were forever raising amendments to Bae , Tornado was similar. Cant believe that the parachute shackle issue hadnt been highlighted long ago as it was the same on a lot of earlier seats. Suspect its been lost in time as i'm sure i remember armourers checking for freedom of movement on those on refit after coming back from the bay. How many of us ever checked a seat handle was in place ? You automatically look for the pin being stowed ! Not any more !