Following your article, we were surprised to note the inclusion of the spabbing as a potential defect caused by 'maintenance and repair'. While you do not qualify whether the statement is a comment on repair technique or philosophy, the comment is highly misleading.
The spab does not advocate a prescriptive repair methodology, but rather the adoption of a pragmatic approach towards defects, based on first-principle examination of problems encountered. If the spab has any specific basis for repair, it would be only to repair the building effectively with the minimum loss of historic fabric.
Clive Richardson's article should be prefaced with the warning that his suggestions are not hard-and-fast rules, but should be adopted following full analysis of the particular masonry defect in hand. In this way his suggested repairs will not be the 'defects in maintenance and repair' of the future.