He was an excellent trader from what I understand. The spoofing was just a side-hobby.....and his programming specifications were just so well done....he nailed it with the "layering" technique. It was so easy to trade with the spoofing algo active.....much easier than trading without.I read the dude made 70 million of which only(!) 13 was due to spoofing. Seems like a legit trading savant.
All in all, the CME Group should come out of this with egg on their face....they could have stopped the spoofing programatically...but didn't.