I stated only that "the majority does not understand how..." etc. etc.
One cannot be sure of anything when it comes to these matters. Also "did much worse" is quite subjective but I do agree that the Soviets and the Germans did perform such experiments as well. Let us not forget that the U.S. probably performed similar experiments. However, the fact that the U.S. granted Shiro immunity for the information gathered at Unit 731 most likely means that the U.S. had not performed tests of the same magnitude and were eager to get information on biological/chemical warfare to get ahead of the ever growing USSR at the time.