Not true with the Thunderbirds.
Some observations:
1) OF COURSE, this is all speculation but this really sounds like pilot incapacitation (probably due to a bird strike) to me. He appears to have throttled back or lost some power, then crashed on a shallow vector. These guys are flying at 350 knots or more, in close formation — and bird strikes are a constant hazard at low altitude. The The FA-18 flight control system features a four-channel, dual computer control-by-wire system with mechanical stabilator backup, and the Blue Angels have the best MX in the fleet — not likely there was a flight control problem.
2) All these posts about pre- fly-by-wire aircraft flight controls such as the A-4, F-4, Fokker DR-1 or whatever are completely irrelevant.
3) This thread needs more facts and less chest-thumping.
more on the flight controls:
http://www.safetycenter.navy.mil/media/approach/vault/articles/2004/0681.htm