Just to clear up a couple of points.
It is very possible to fit the seat pan pin into the seat housing with the handle displaced,this has happened before on a different aircraft type within the last 12 years.
As others have said - straps / neg g straps have been wrongly routed within the last 5 years on hawk aircraft during strap in !
Finally to help deflect the conspiracy theory - I would just like to say that except for during seat maintenance (ie deeper than line maintenance) the ONLY person who touches the seat pan pin is the pilot/aircrew occupying the seat...NOBODY else would dare touch the pin - it is absolutely drilled into all groundcrew that we do not touch the seat pan pin...and there is absolutely no need for us to touch that pin !
Also to say that at some units - if the aircraft is serviceable and will be flying
the next day or pretty soon - the seat pins are not moved from pins park to pins serv/maint !I am not saying that the reds do this but some units do !