了 as "perfect" aspect vs 了 as "actual" aspect theory
Answering your new edited question.  Your first reference, "Aspect in Mandarin Chinese: A Corpus-based Study" by Richard Xiao,Tony McEnery, indeed gives a novel fine-grained analysis of perfective particles in Mandarin.  But it is their own theory and so far as i can see more people cite it than expand on it. A list of 186 works citing it is given at https://scholar.google.com/scholar?oi=bibs&amp;hl=en&amp;cites=14017749010703840750&amp;as_sdt=5

The issue here is grammaticalization.  If we want to say 了 has a purely grammatical role in the sentence 我吃了 then we obviously cannot just say that role is as a perfect aspect marker.  The word clearly does more than indicate perfect aspect.  So we must define some much more specific subdivision of perfect aspect like "actuality aspect."  But other grammarians prefer not to subdivide aspect that way, and rather say 了 has a lexical or pragmatic role in addition to its grammar.  There is a vast literature on this, and references in Michaelyus answer are one good way into it.