In reply to:

Not sure about those who *build crossword puzzles, but there is widely believed to be a negative correlation between being good at crossword puzzles and being good at Scrabble®.

Interesting. Maybe it is because of all the common nouns and other idiosyncratic words used in a crossword puzzle that are not allowed in a Scrabble game. I once listened to an interview with several championship Scrabblers on the radio. People would phone in to offer jumbled words, and these guys could unscramble these huge words in the time it takes me to clear my throat. Apparently they memorize long lists of words of various letter lengths and various combinations.