The point where they will loose their edge can still come. JWH was also successful for years. But on the other hand these few traders can also be the exceptions to confirm the rule. Future will tell.
My point was that JWH was a good trader, but only traders that are successful now are relevant as proof of things that do or do not work. Past performances have no value for present situations if at present these performances are not there anymore.
Don't all these traders use a kind of TA? Big amounts of money have to be managed by maths, you cannot managed it on "fingerspitzengefuhl" and "other things".
I think especially Simmons is more a TA guy as he works purely on maths.