I got a mail from Gerrit with the above subject.

Just to put my 2 cents: while this change may help the regex to be more readable, such changes in high-scale may harden the transforming of regexes between Pywikibot format and AWB format, and we have a Phab ticket about the cooperation. As we use more Python-specific regexes, the Pywikibot users and AWB uers may be able to help each other less on bot owners' noticeboards.

This is not a critics, just a point of view which may worth to consider.

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