My doubt is whether a digit can be inserted where there could be a word, but not one that produces a solution.

Well. I think it is perfectly clear. You cannot use a digit at any point where a word is available. (*)

(*) I was about to add 'regardless of whether a solution can be achieved', but it is unnecessary. If there is a word available, you cannot ignore that word and use a digit. For any reason, including achieving a solution that would otherwise be complient.

For the record, without that rule, there would be many more solutions that are presented in the official results.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^4: One for the weekend: challenge by BrowserUk
in thread One for the weekend: challenge by BrowserUk

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