well, I'm still learning, thanks to my current instruction which is specifically about what your asking....
basically, these are the first questions to ask:
1. range - what is the distance from opponent you are interpreting? (the Unsu kata clip you mention was sparring range. not likely the range kata addresses.)
2. direction - where is the attack coming from? (the Unsu clip showed the person always turning toward the direction of attack. too slow.)
3. Does it address multiple attacks ie: combos? or are all the incomming attacks a single straight punch? (Unsu clip was with totally complient uke)
4. Where do the sequences start and end? (the clip showed nothing more than the kata being broken up into single block/strike sequences)
there are more, but hey...it's not mine to give away...
refer to these articles written by Giles Hopkins that deal specifically with your question and the hints I put up:
article: "The lost secrets of Okinawan Goju-ryu: What the kata shows," Journal of Asian Martial Arts, Vol 11, #4, 2002.
article: "The shape of kata: The enigma of pattern," Journal of Asian Martial Arts, Vol 13, #1, 2003.
article: "The teaching of Goju-ryu kata: A brief look at methodology and practice," Journal of Asian Martial Arts, Vol 14, #2, 2005.
you can get them here:http://www.goviamedia.com/journal/issues.html
in general, if I see kata application that is against a long-range attack from 2 perfectly timed opponents striking at the same time in opposite directions, defending with just their arms while not even able to see the other opponent....yep, I'm gonna pick on it.