Scrabble and Retrograde Analysis

Reading Mike Keith's article "Scrabble-Tile Double Word Squares and Rectangles" (WW Feb 2011) led me to ask the following question: which of the word grids he gave are actually legal positions in a game of Scrabble? Chess problemists use the term "retrograde analysis" for the stud?, of how chess positions might have arisen in a legal game; this concept is of course equally applicable to other games, including Scrabble. I should say, for the benefit of readers who may wish to pursue any of the questions I ask, that when writing this article I have not attempted to consult any online word lists; all the words used here are either words I know or words used in Mike Keith's article.