Does raising speaker cables off the floor really make a big difference?

Oh gee...that's hilarious. You spent way too much time on that  considering how unfunny it was.

Yes it took me months to try this all out. And a few minutes to report back. 

I have had mine raised off the carpet floor for about a month, could not tell the difference. I moved them back to the floor with out the risers and the sound did change a little, i put them back on the risers for the better. 

Good point. Testing sometimes requires a more careful and thorough approach. People oft jump to conclusions too quickly.