Merge/consolidate categories and tags

Tired of seeing duplicated categories on your WordPress site (with all the side-effects this provokes, like not being able to easily count all the posts of a “category” since in fact, that category, is repeated several times, each one used to classify a subset of all relevant posts for the category)?

We offer the possibility of consolidate all these repeated categories by 1 – removing the duplicates and 2 – assigning to this single category/tag all posts that were before assigned to one of the duplicates.