I've spoken to the Dak crew involved:
1. The venue, Netherthorpe, asked for a FLYPAST and if you read GASOs you will see that crowd-line does not come into it.
2. If you read GASOs further you will see that the minumum height for flypasts is 250'MSD.
3. "Dog and Pony" events like that at Netherthorpe often publish display and crowd-lines when requesting flypasts from military aircraft which really do not apply. If they published and broadcast that the Dak was displaying then they are wrong as all it was authorised to do was a couple of flypasts and then depart.
4. The DISPLAY sequence as authorised by the AOC involves a 100' fly-through, followed by 300' 360 degree turn then a slow and configured fly-through and then a final 100' fly-through in the opposite direction to the arrival - There are to be no changes to this. Is this waht you saw? - Ivery much doubt it!
So for my not-so-learned friend who started this thread, you may have been mislead by the commentator at Netherthorpe, you may have seen what you thought was a display (But was actually a perfectly legal flypast) and you ARE wholy incorrect.
LJ