Originally Posted by
DaveReidUK
That sounds to me like it's a genuine door, only deactivated (and which can be reactivated), rather than a dummy one.
It is a genuine door frame, stripped of the slide, internal paneling and opening mechanisms. The locks are bolted in place and in principle should not be able to move. (Of course if any of those bolts were missing...). 'Reactivation' is a tad more than pulling a safety inhibitor pin, but still much less effort than cutting a hole in the fuselage and installing the required hardpoints.