The reasonable and ethical engineering approach is to do one's best with models, simulations, first principles analysis and design something that works on paper

The reasonable and ethical engineering approach is to do one's best with models, simulations, first principles analysis and design something that works on paper. And then built prototypes, test the hell out of them. Without people inside. Standardize everything they can about manufacturing. If all looks good, they can operate. Never stop measuring and testing. The operators decided this was too much work. They gambled and they lost.