Err Max, I thought you flew for us? We don't use a nose gear lock pin for pushback! certainly not here at LGW.
The whole point of the mechanism is that it is over-centre. In order to break, it has to go through the centre, inline position so that it can pivot in the normal way and therefore allow the gear to retract. Any pressure on it will tend to increase the over-centre pushing against the lock stops in the opposite direction to that which is required to retract the gear.
I have had to manually break the lock to retract the gear in order to allow a nose leg seal change. It takes a 5 foot bar and a good heft to get the lock back through overcentre to allow the gear to retract with no hydraulics applied and I'm 6'3" and 100 Kgs.
