Camera recordings of previous flights indicate that the pilot did not fly the display sequences as accurately as might be desired. There appears to have been a tendency to fly manoeuvers a bit lower than the ideal. So something of a habitual pushing of the limits? Makes for more exciting viewing from the ground, but no room for error if things go wrong, as they did at Shoreham.
If that statement is correct (IF) then the 'something happened to the pilot' scenario looks less likely.
It may be suggested that any pilot involved in a display carrying out manoeuvres outside of the safety criteria - even if he gets away with it - should be banned from further display. At any display there will be enough experienced pilots around to be aware when safety measures are stretched.