Wrapping and tension - What is the right amount of tense?

Sifu Kelley,
I have a question regarding relaxation (as is explained on pg 26 of the ILC manual) and wrapping. I understand such relaxation to be at a level that allows the maintenance of correct structure. So, there is some tension implicit here – i.e. that which is necessary to maintain the structure. When I practice wrapping, I have the intention of rotating hands and feet outward and this intention adds a layer of tension. I can assume basically the same structure as I do in wrapping, but instead, relax into my structure – when I do this I feel less tension than with the wrapping exercise. 
 
Am I adding unnecessary tension to the wrapping drill or are wrapping and relaxation intended to be different?
 
If wrapping implies more tension, then to what purpose?
 
Thank you