Yes, a flawed deign in many ways, but what design isn't?
Rutan and Roncz understood intersection drag. If they calculated that it would go fast, and they have a history of meeting their goals, I believe them. I think that the auto engines were the real flaw in the concept. They never put out the intended power, partly I think because of the limitations of the power plant installation itself. I've never seen another plane that needed leaf blowers for ground cooling!
Virtually every time they ran the engines hard one caught fire and there were multiple reasons.
I think they ran gasoline exclusively (as I understand) after the Rutans stepped out of the race team. When Rick crashed it was on gas.
One of the causal factors of the crash was the poor sealing between the nacelles and the cockpit (one of those design flaws) allowing smoke to enter the cockpit. Rick was not running 100 percent oxygen and the smoke he inhaled probably contributed to impaired judgement/skills during the landing phase. He was killed in the fire, but was likely unconscious from the severity of the impact and the elevated carbon monoxide level in his bloodstream.
Rick was a really nice guy and his death had quite an impact on Bob Pond (and many others of course). Rick flew A-7s in the guard and was also a scale R/C champion in his youth. He gave me my first ride in a P-51.
http://dms.ntsb.gov/aviation/AccidentRe ... 120000.pdf