I went to a couple of Breakfast Patrols at Goodwood back in the early 80's, and good fun they were as well.
Provided everyone realises it is done for entertainment and not combat things do not normally degenrate into low flying rule breaches or dangerous manouevres.
The most avoiding action I ever took was to turn towards the defender so as to hide the reg's on the side and under the wing of the machine. This usually results in the two of you chasing each other around a circle until someone gets bored (normally the attacker who is missing out on breakfast).
I was successful on both attacks but duly put the price of a breakfast in the Goodwood Club coffers to pay something towards the cost of running such an event.
I think many breakfast patrols have dissapeared for 'environmental' reasons, not wishing to disturb the natives below with aeroplanes rushing around over noise snesitive areas.
Regards
TMC