I have to ask - does the same theory apply to directional interconnects? I honestly don't know but have never heard a difference.
Directional interconnects depends on what specific type of interconnect we are discussing.
There have been a number of arguments about dropping the ground from one end of a connection to help keep ground loops from coming into play. So, a cable that employs this will be directional in that regard. It won't necessarily help the audio in any way in a system that doesn't have any issues with grounding at all. But, it may help in a system that has ground issues.
HDMI interconnects that are listed as 'directional' are a COMPLETELY different matter! HDMI has cables which employ active digital chips inside of them which maintain a proper signal. These chips don't change the signal, or improve/hurt the signal, they just maintain the original signal over the distance required. So, they are awesome at doing their job and a great way to go if you want a ultra-slim HDMI cable that can handle 18Gb/s bandwidth.
People are quick to dis' things that may sometimes make more sense with more knowledge, so it's important to be specific.
The flip side to directional audio interconnects is the 'active' ones, which, AFAIK, should be avoided at all times. A battery on a audio interconnect isn't going to be doing good things, but it may very well be directional... just not good.