Time have changed. The most common question I've heard when it comes to Thoughtseize is, "What about the life-loss, is it an issue?" The quick answer is no. Storm decks for the last seven years have ran four copies of Gitaxian Probe and have done just fine. The trade-off of two life and being able to hit anything instead of "non-creature, non-land" is why you see four copies of Thoughtseize in every list, while lists fluctuate between three and four copies of Duress. Being able to have a guaranteed hit against Thalia, Guardian of Thraben or Ethersworn Canonist without question is extremely valuable compared to a blind Cabal Therapy against a deck like Death & Taxes or guessing the proper counterspell against blue decks. While The EPIC Storm will miss the synergies between Cabal Therapy, Gitaxian Probe, and Goblin tokens, I'm a firm believer that Thoughtseize will carry us into the future.