• Friend-of-a-Friend (FOAF) is, as far as I know, not a W3C recommendation, although some of the authors also participate in W3C activities.
• To count RDF as an ontology is not correct. Table 1 seems to mix apples and oranges (RDF, RDF-S, and FOAF).
• Figure 4 is very confusing; it might be that I missed something there, but how was this figure generated?
• On page 95, Hepp states that "the experiment details are described elsewhere," but the reference points to citation 6, which is obviously not the correct source — I'd be very interested in the original work that Martin is referring to, there.
• To take the sheer size of an ontology as a metric for its expressivity is (carefully stated) questionable. In case an ontology is well documented — has, for example, many <rdfs:comments> in — it will get big, no matter how many concepts or props you've defined in there.
• The CPU use case didn't add much. I don't see the message in this paragraph.
An example of the former is to say, 'I believe the W3C that their definition of foaf:knows in the Friend-of-a-Friend vocabulary specification is compatible with my definition; if there are discrepancies, I'm willing to take the consequences.'
To count RDF as an ontology is not correct. Table 1 to me seems to mix apples and oranges (RDF, RDF-S, and FOAF).
• The effort for reviewing the specification for potential adopters increases with the size of the specification document.
• The effort for maintaining a specification in a quickly evolving domain increases with the amount of detail per element.
• The effort for reviewing an updated version of the standard prior to migrating to this new version increases with the specification's overall size and thus limits the amount of people who are willing to spend the respective effort.