This is very common knowledge among older, more experienced, more advanced audiophiles.
Mr. Pierre Sprey does a nice synopsis, called " Wire Management" on his "Mapleshade Audio" web site.
The CARDAS CCGR speaker posts design eliminates all of this problem, and are about as good ( sonically ) as I know of.
Yes, I am showing you a problem, and also offering all a correct solution.
The metrics we use is our negative experience with plastics ANYWHERES touching
or near a good speaker cable ( in a good system ), common sense from this experience, and our ears.
Good questions !! Thanks.
drlowmu