Amire, you are clearly abusing your admin privilege, by administratively deleting an answer (and hiding its content in the history) that was on completely topic, and no so long as you state. It also explained what could be done for now and what may eventually be done in MediaWiki to solve such problem.
You say it was not replying the question. But what was really the question? The current lack of support in Mediawiki and the way it works and how error trackings in categories may (or may not) be done in the result of a parser function that is not supposed to return such thnig in the plain-text format (excluding MediaWiki and HTML tags) expected in return by this function.
As your question has no definitive answer for now, I explained a workaround, currently used in many templates (and their possible caveat, minor in most existing usage cases, using "#iferror"). And it was properly formatted. It's not my answer that is too long, but your question which is badly formulated, and is in fact exposing a problem, seeking for solutions or workarounds (what I did). If you don't want any opinions exposed to this case, why posting here to the public? I did not violate any rule here, but you just did it with your privileges.