Thanks for the replies. Yes, I'm sure that in an ideal World two cables would be best but considering the cost of some of these cables,this can be prohibitive, so I'll continue as I am.
Bi-amping with Audioquest cables
Owners of Audioquest hyperlitz cables will know that these cables are made up of multi-strand wires, which are individually insulated. This makes the job of bi-wiring more effective and quite straight-forward. In spite of this, Audioquest have told me that they should not be used for bi-amping (ie two pairs of bass and treble wires at both speaker and Amp ends,)but instead, I should use TWO pairs of cables. Nevertheless, before I was advised of this, I had in fact configured a single pair of their Indigo cables into a a bi-amp set up and still use them like this to this day with good effect. I have now managed to pick up a pair of their Moonlight cables which are currently single wired and am considering re-wiring them the same as the Indigo's. Does anyone know why I shouldn't be doing this? Could this cause problems with Impedence?(I have emailed Audioquest but to date not had a reply).