"Abusing the mike", so he said to explain why. I don´t know where I read or heard that.
Recently he gave another reason. On reading the audiobook of Georgette Heyer´s The Convenient Marriage he said (paraphrased) to like to read "words that mean the same but feel differently in the mouth". Could have sworn he mentioned in some interview the phrase "tasting the words in my mouth" or my mind turned it into that.
Didn´t think for a minute it could have something to do with really associating a taste with a word, a condition called lexical-gustatory synesthesia. It is triggered by the phonemes in the word, rather than graphemes or it could be that it´s from semantic influences.