Emcee, I’m pleased that you have spelled out the issue that I was hinting at in my message. The wording of the preamble very strongly implies that there is a chain of alterations in which, at each stage, a non-word must be altered to become a real word. The use of the word, ‘triggers’ and the phrase, “to make it a real word” (rather than ‘resulting in another word’) make it hard to read it any other way, and the phrase, ‘and so on’ implies a continuing pattern. At the very least, the meaning that appears to be the intended one is not a natural reading. Despite upsetter’s use of ‘bleating’ I don’t think it’s an unfair criticism at all. I spent a long time exploring other routes, thinking that Pointer may have devised a very cunning route that does involve altering non-words at each stage, but I think a close examination of the last two or three altered entries reveals that it’s not possible. However, I still harbour doubts. Given the flexibility of an asymmetric grid and split entries I’m surprised that an experienced and skilled setter didn’t achieve the ideal consistent pattern. He shouldn’t be criticised for not achieving that ideal if it wasn’t possible, but the preamble should not appear to suggest he has.
On another matter I’m puzzled by Cruncher‘s reference to an obscure final entry for 9a. Mine is a common word. Either my solution is wrong or there would be appear to be an alternative solution.