Should Scrabble letter values be changed?

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Joshua Lewis is a postdoctoral researcher at the University of California, San Diego.
     He thinks that although Alfred Butts' original research, in the 30s, of the frequency of letter distribution used to assign values to Scrabble letter tiles remains largely accurate, some values should be tweaked.
     Lewis considered frequency of letters, frequency of word length and ease of transitioning.
     He thinks, for example, that the letter X, worth 8 points, should be devalued to 5.
     Mattel, current owner of the game, says it has no plans to change letter values.