Well, Cricket, many gifted kids are good guessers, as in, making good inferences. I wouldn't dismiss a kid who guessed well enough to get a high WISC score.

I'm aware of the controversy about EM. Several newer math programs try to get away from memorization/standard algorithms and towards a conceptual approach. Just google "fuzzy math" and you'll get more of the same criticisms. All I can say is that so far, DD11 and DS5 are excelling in math - not sure if that's in spite of or because of EM.