In fact, I never really understood why you would collect both Shorin and Goju into one system. Isn't there redundancy of some kind at the very least? From the list in McCarthy's book there are 52 kata in Mabuni's Shitoryu system. How can one practice, let alone fully understand, so many kata? I've had occasion to talk to Shitoryu black belt instructors, and they have confessed that their knowledge of many of these kata is at best "rusty."
Mabuni's second sequence is equally questionable it seems to me. He doesn't show the cat-stance fist-in-palm technique that immediately follows the last technique in the first sequence and precedes the first technique in this second sequence. Then he seems to show the two-handed technique as a push against the opponent, who then seems to advance once more and is attacked with an elbow to the mid-section. Not to say that these technique would be completely ineffective but there are a number things that seem unrealistic about them. Why would one push the opponent away just to allow him to attack again? Again, in the kata, the left open palm is cupped over the right elbow. Is this one of Mabuni's "varied interpretations"? I much prefer to see this sequence as a continuation of the previous sequence of moves.