Artist,
you forgot to quote the previous sentence :
"A few months later this gyro-copter and its owner came to fatal termination performing some manoeuvre outside of its ill-defined flight envelope."
Very interesting experience, i feel that it shows the positive aspects of gyro flying.
Now, if someone gets out the flight envelope, may it be in a gyro, a helicopter or a bicycle : he may crash !
You can't say a B47 is not safe because a lot of crop sprayers had severe crashes ... you just can say they were close to the flight enveloppe boundaries.
The post you link to also , IMO, calls to not let the gyro to the only "small bands of enthusiasts"
thanks you