Sure, but isn't this as much an argument for efficient markets as anything. Literally hundreds of thousands of folks have died on the very hill Medallion is ho

Sure, but isn't this as much an argument for efficient markets as anything. Literally hundreds of thousands of folks have died on the very hill Medallion is holding. The fact that there is just one firm with this track record is evidence that markets are pretty hard and relatively efficient. Whether markets are so perfectly efficient that no firm can really beat the market, well that just seems like a pretty academic and unhelpful question. You don't need some grand perfect market hypothesis to say 'man those returns look a bit too good to be true, what's really going on in there?"