That post refer to 24 words recovery phrase generated by Ledger. But he's being paranoid since brute-forcing 24 words combination with 2048 words as dictionary is very expensive. It's different case if he don't trust RNG on Ledger.
I know and have tried using rotorcuda and fialka to run random private key attacks and trying to find private keys. In fact, I have already found a few private keys (unfortunately they were already emptied before by someone else).
Did you run it randomly or on very specific range?