Every government letter should come with a “Glossary of Acronyms” (GOA), attached so we can tell WTF they are talking about.
Acronyms enable incoherence. That is the goal and it nicely turns understanding into a damn slog.
I get large specification documents with just what you describe, in index of acronyms. Typically i get as many as twenty such specs in one package.
Each has an index of acronyms....... they are not the same. Each spec has many unique entries. The total is almost incomprehensible