I've read different things so maybe there is some confusion on my part. My understanding is that if you have one cable with two conductors within a sheath, that is a single "wire". If you have a pair of independent conductors (one signal and one return), that is called a "shotgun" run. If you have two paths from the amp to the speakers (one for the upper and one for the lower) that is bi-wire. So a regular bi-wire is two cables and a shotgunned bi-wire is four independent cables.
Those Speltz cables are a shotgun pair. Biwiring using two sets of those is shotgun bi-wire. That is supposed to be the ultimate.
In my case, I had been using MIT MH750 for the Thiels and Tara Lab TSII to my sub. According to my understanding above, the former is a single run and the latter are shotgun single run. Since I took the sub out of the system, what I have now is a cluster fuck bi-wire: non shotgun to the monitors and shotgun to the bass cabinets.
I tried both ways - using the data-links and biwired, and I heard an improvement with the bi-wire arrangement over the single wire arrangement. I also tried swapping the Taras and the MITs between the two cabinets and I do not recall hearing any significant difference.
Lately I've been really happy with the CVH Pulsar and the Z-Squared ICs. Chris is supposed to announce a new speaker cable in the next month or so. I want to try those or the Z-Squared (but I'm sort of afraid to call Z-Squared for a quote).