There was a recent BBC Horizon episode called 'Do you see what I see?'
Colour perception varies from person to person, between sexes and different age groups; it is also mood dependant. None of us sees colour in exactly the same way!! This is a startling revelation to me, in fact most colour information is more down to the brain than what is actually present with the exception of blue and yellow which is hard encoded into our make-up.
Some people could well prefer Dynamic mode on their TVs, over other modes.
This may well account for some people seeing differences between HDMI cables. There is no absolute in visual perception - we are all different!
So what you see is not what I see!
I've lost count of the arguments I've had where people want me to prove what I am seeing with regards to say AV cables. I can no more prove how my brain decodes colour information than they can! doh!