There is no going back now. The regulators, the MAA, the AAIB, almost everyone who is directly involved in airshows has re-written the rule book. Risk is uppermost in everyone's mind and mark my word, the next time this happens (a major incident- at an airshow), the roof will come tumbling in and they will not take prisoners.
Example - the RAFAT have done their best to apply their display axis (from a safety perspective) to each and every venue that requests them.
However, it is the Event Organiser (EO) who MUST own this risk on the day.
He/she must risk management the predetermined display to ensure the terrain over which they fly is safe (secondary crowds).
Parts of the RAFAT display comply with SERA 5005(f), so shouldn't be an issue - but where RAFAT have an alleviation to SERA 5005(f) it is up to the EO to decide whether they want to invite this "risk" to their neighbourhood.
If they do - they must apply "reasonable" efforts to mitigate the risk to 2ndary crowds.
Failure to do so will be perceived by the Authorities to be an act of negligence. [If something goes wrong].
Make no bones about this.
Problem is: what is reasonable?
Only two types of people rule the world: Lawyers and Accountants.