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

Yes, at very least it keeps your cables clean, and makes it easier to clean the floor.

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

I think that rather than wondering if it makes a sonic difference, we should all be doing it to keep dust bunnies away from our expensive cables. Before I used the homemade ones that I now use I would have dust collecting all over them.

Not funny.

It doesn't make a big difference in my system, but it does make a small positive difference, and besides that, you protect your expensive cables from dust bunnies.