Did you read the article? They explained why an implementation of RDRAND as "XOR together the contents of all registers and return it" would result in removing nearly all of the entropy in the state vector. And it proposed a simple solution: modify the code so that the hardware entropy is mixed in earlier in the process (in which case it WOULD require the prodigious feats you are talking about).
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Did you read the article? They explained why an implementation of RDRAND as "XOR together the contents of all registers and return it" would result in removing nearly all of the entropy in the state vector. And it proposed a simple solution: modify the code so that the hardware entropy is mixed in earlier in the process (in which case it WOULD require the prodigious feats you are talking about).