What is a Powerful Kata? How can one observe a powerful kata?

A blogger made this statement, "When I observe a strong kata, I think: I really would not want to get hit by that person." It made me ask, "how can one observer power in a kata?" The following is my possible answer(s):

How can you observe a strong kata? What constitutes an outward manifestation of what is called a "strong kata?" An interesting question because I wonder if the person is looking for so called telltale signs of power. Isn't it reality that true power manifests itself as "not powerful looking" if applied correctly?

In The Book of Martial Power is is quoted as, "The Power Paradox." Defined in the book as, "true power feels, and actually should be, effortless AND that which feels like powerful exertion is not." Does this mean that one should not or cannot actually observe a strong kata?

Or, maybe looking at it another way is that the person who said he liked to observer a strong kata as in the quote means that his observation does NOT detect what is normally thought of as power or powerful kata.

Maybe they meant that if the kata is strong it merely displays good stances, good stance transition; applied techniques as appropriate with momentum, speed and power; maybe observing powerful kata is the observation of good posture, body alignment, economy of motion, structure. If this is what was meant then yes, I would not want to be on the receiving end of that karate-ka if they were going to hit me.

Bibliography:
Perlman, Steven J. "The Book of Martial Power: The Universal Guide to the Combative Arts." New York. The Overlook Press. 2006.