I've got a similar story to Trim Stab. Flying a Citation into Luton one of our pax stood behind us in the descent and started asking lots of questions and generally acting quite anxious. One question was 'Have we got enough fuel ?'. Turned out he was looking at the fuel flow gauges.
The Captain was very good with him and persuaded him he needed to get back into his seat and strap in as we would be landing in a few minutes.
When we landed, as soon as the aircraft stopped, the pax got up, opened the cabin door and strode straight off across the busy apron !
